XmlSerializer Constructors

protected:
 XmlSerializer();

protected XmlSerializer();

Protected Sub New ()

public:
 XmlSerializer(Type ^ type);

public XmlSerializer(Type type);

new System.Xml.Serialization.XmlSerializer : Type -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een XmlSerializer object met de naam Widgetgeserialiseerd. In het voorbeeld worden verschillende eigenschappen van het object ingesteld voordat de Serialize methode wordt aangeroepen.

private void SerializeObject(string filename)
{
   XmlSerializer serializer =
   new XmlSerializer(typeof(OrderedItem));

   // Create an instance of the class to be serialized.
   OrderedItem i = new OrderedItem();

   // Set the public property values.
   i.ItemName = "Widget";
   i.Description = "Regular Widget";
   i.Quantity = 10;
   i.UnitPrice = (decimal) 2.30;

   // Writing the document requires a TextWriter.
   TextWriter writer = new StreamWriter(filename);

   // Serialize the object, and close the TextWriter.
   serializer.Serialize(writer, i);
   writer.Close();
}

// This is the class that will be serialized.
public class OrderedItem
{
   public string ItemName;
   public string Description;
   public decimal UnitPrice;
   public int Quantity;
}

Private Sub SerializeObject(ByVal filename As String)
    Dim serializer As New XmlSerializer(GetType(OrderedItem))
    
    ' Create an instance of the class to be serialized.
    Dim i As New OrderedItem()
    
    ' Set the public property values.
    With i
        .ItemName = "Widget"
        .Description = "Regular Widget"
        .Quantity = 10
        .UnitPrice = CDec(2.3)
    End With
    
    ' Writing the document requires a TextWriter.
    Dim writer As New StreamWriter(filename)
    
    ' Serialize the object, and close the TextWriter.
    serializer.Serialize(writer, i)
    writer.Close()
End Sub


' This is the class that will be serialized.
Public Class OrderedItem
    Public ItemName As String
    Public Description As String
    Public UnitPrice As Decimal
    Public Quantity As Integer
End Class

Opmerkingen

Meestal definieert een toepassing verschillende klassen die het XmlSerializer converteert naar één XML-exemplaardocument. Het XmlSerializer moet echter slechts één type kennen: het type van de klasse dat het XML-hoofdelement vertegenwoordigt. Hiermee XmlSerializer worden alle onderliggende klasse-exemplaren automatisch geserialiseerd. Op dezelfde manier is alleen het type XML-hoofdelement vereist voor deserialisatie.

Zie ook

• Serialize(TextWriter, Object)
• Deserialize(Stream)
• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(System::Xml::Serialization::XmlTypeMapping ^ xmlTypeMapping);

public XmlSerializer(System.Xml.Serialization.XmlTypeMapping xmlTypeMapping);

new System.Xml.Serialization.XmlSerializer : System.Xml.Serialization.XmlTypeMapping -> System.Xml.Serialization.XmlSerializer

Public Sub New (xmlTypeMapping As XmlTypeMapping)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een klasse met de naam Groupserialiseren. De serialisatie van de GroupNamevelden IgnoreThis en de leden van de GroupType opsomming worden overschreven. In de CreateOverrideSerializer methode wordt een SoapAttributeOverrides object gemaakt en voor elk overschreven lid of opsomming wordt een SoapAttributes object gemaakt met de juiste eigenschappenset en toegevoegd aan het SoapAttributeOverrides object. Er XmlMapping wordt een object gemaakt met behulp van het SoapAttributeOverrides object en dat XmlMapping object wordt gebruikt om de XmlSerializer standaardserialisatie te vervangen.

using System;
using System.IO;
using System.Text;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Schema;

public class Group
{
   [SoapAttribute (Namespace = "http://www.cpandl.com")]
   public string GroupName;

   [SoapAttribute(DataType = "base64Binary")]
   public Byte [] GroupNumber;

   [SoapAttribute(DataType = "date", AttributeName = "CreationDate")]
   public DateTime Today;
   [SoapElement(DataType = "nonNegativeInteger", ElementName = "PosInt")]
   public string PostitiveInt;
   // This is ignored when serialized unless it's overridden.
   [SoapIgnore]
   public bool IgnoreThis;

   public GroupType Grouptype;

   public Vehicle MyVehicle;

   // The SoapInclude allows the method to return a Car.
   [SoapInclude(typeof(Car))]
   public Vehicle myCar(string licNumber)
   {
      Vehicle v;
      if(licNumber == "")
         {
            v = new Car();
        v.licenseNumber = "!!!!!!";
     }
      else
     {
       v = new Car();
       v.licenseNumber = licNumber;
     }
      return v;
   }
}

// SoapInclude allows Vehicle to accept Car type.
[SoapInclude(typeof(Car))]
public abstract class Vehicle
{
   public string licenseNumber;
   public DateTime makeDate;
}

public class Car: Vehicle
{
}

public enum GroupType
{
   // These enums can be overridden.
   [SoapEnum("Small")]
   A,
   [SoapEnum("Large")]
   B
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeOriginal("SoapOriginal.xml");
      test.SerializeOverride("SoapOverrides.xml");
      test.DeserializeOriginal("SoapOriginal.xml");
      test.DeserializeOverride("SoapOverrides.xml");
   }
   public void SerializeOriginal(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlTypeMapping myMapping =
      (new SoapReflectionImporter().ImportTypeMapping(
      typeof(Group)));
      XmlSerializer mySerializer =
      new XmlSerializer(myMapping);
      Group myGroup=MakeGroup();
      // Writing the file requires a TextWriter.
      XmlTextWriter writer =
      new XmlTextWriter(filename, Encoding.UTF8);
      writer.Formatting = Formatting.Indented;
      writer.WriteStartElement("wrapper");
      // Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup);
      writer.WriteEndElement();
      writer.Close();
   }

   public void SerializeOverride(string filename)
   {
      // Create an instance of the XmlSerializer class
      // that overrides the serialization.
      XmlSerializer overRideSerializer = CreateOverrideSerializer();
      Group myGroup=MakeGroup();
      // Writing the file requires a TextWriter.
      XmlTextWriter writer =
      new XmlTextWriter(filename, Encoding.UTF8);
      writer.Formatting = Formatting.Indented;
      writer.WriteStartElement("wrapper");
      // Serialize the class, and close the TextWriter.
      overRideSerializer.Serialize(writer, myGroup);
      writer.WriteEndElement();
      writer.Close();
   }

   private Group MakeGroup(){
      // Create an instance of the class that will be serialized.
      Group myGroup = new Group();

      // Set the object properties.
      myGroup.GroupName = ".NET";

      Byte [] hexByte = new Byte[2]{Convert.ToByte(100),
      Convert.ToByte(50)};
      myGroup.GroupNumber = hexByte;

      DateTime myDate = new DateTime(2002,5,2);
      myGroup.Today = myDate;
      myGroup.PostitiveInt= "10000";
      myGroup.IgnoreThis=true;
      myGroup.Grouptype= GroupType.B;
      Car thisCar =(Car)  myGroup.myCar("1234566");
      myGroup.MyVehicle=thisCar;
      return myGroup;
   }   	

   public void DeserializeOriginal(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlTypeMapping myMapping =
      (new SoapReflectionImporter().ImportTypeMapping(
      typeof(Group)));
      XmlSerializer mySerializer =
      new XmlSerializer(myMapping);

      // Reading the file requires an  XmlTextReader.
      XmlTextReader reader=
      new XmlTextReader(filename);
      reader.ReadStartElement("wrapper");

      // Deserialize and cast the object.
      Group myGroup;
      myGroup = (Group) mySerializer.Deserialize(reader);
      reader.ReadEndElement();
      reader.Close();
   }

   public void DeserializeOverride(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer overRideSerializer = CreateOverrideSerializer();

      // Reading the file requires an  XmlTextReader.
      XmlTextReader reader=
      new XmlTextReader(filename);
      reader.ReadStartElement("wrapper");

      // Deserialize and cast the object.
      Group myGroup;
      myGroup = (Group) overRideSerializer.Deserialize(reader);
      reader.ReadEndElement();
      reader.Close();
      ReadGroup(myGroup);
   }

   private void ReadGroup(Group myGroup){
      Console.WriteLine(myGroup.GroupName);
      Console.WriteLine(myGroup.GroupNumber[0]);
      Console.WriteLine(myGroup.GroupNumber[1]);
      Console.WriteLine(myGroup.Today);
      Console.WriteLine(myGroup.PostitiveInt);
      Console.WriteLine(myGroup.IgnoreThis);
      Console.WriteLine();
   }
   private XmlSerializer CreateOverrideSerializer()
   {
      SoapAttributeOverrides mySoapAttributeOverrides =
      new SoapAttributeOverrides();
      SoapAttributes soapAtts = new SoapAttributes();

      SoapElementAttribute mySoapElement = new SoapElementAttribute();
      mySoapElement.ElementName = "xxxx";
      soapAtts.SoapElement = mySoapElement;
      mySoapAttributeOverrides.Add(typeof(Group), "PostitiveInt",
      soapAtts);

      // Override the IgnoreThis property.
      SoapIgnoreAttribute myIgnore = new SoapIgnoreAttribute();
      soapAtts = new SoapAttributes();
      soapAtts.SoapIgnore = false;
      mySoapAttributeOverrides.Add(typeof(Group), "IgnoreThis",
      soapAtts);

      // Override the GroupType enumeration.	
      soapAtts = new SoapAttributes();
      SoapEnumAttribute xSoapEnum = new SoapEnumAttribute();
      xSoapEnum.Name = "Over1000";
      soapAtts.SoapEnum = xSoapEnum;

      // Add the SoapAttributes to the
      // mySoapAttributeOverridesrides object.
      mySoapAttributeOverrides.Add(typeof(GroupType), "A",
      soapAtts);

      // Create second enumeration and add it.
      soapAtts = new SoapAttributes();
      xSoapEnum = new SoapEnumAttribute();
      xSoapEnum.Name = "ZeroTo1000";
      soapAtts.SoapEnum = xSoapEnum;
      mySoapAttributeOverrides.Add(typeof(GroupType), "B",
      soapAtts);

      // Override the Group type.
      soapAtts = new SoapAttributes();
      SoapTypeAttribute soapType = new SoapTypeAttribute();
      soapType.TypeName = "Team";
      soapAtts.SoapType = soapType;
      mySoapAttributeOverrides.Add(typeof(Group),soapAtts);

      // Create an XmlTypeMapping that is used to create an instance
      // of the XmlSerializer. Then return the XmlSerializer object.
      XmlTypeMapping myMapping = (new SoapReflectionImporter(
      mySoapAttributeOverrides)).ImportTypeMapping(typeof(Group));
    
      XmlSerializer ser = new XmlSerializer(myMapping);
      return ser;
   }
}

Imports System.IO
Imports System.Text
Imports System.Xml
Imports System.Xml.Serialization
Imports System.Xml.Schema

Public Class Group
   <SoapAttribute (Namespace:= "http:'www.cpandl.com")> _
   Public GroupName As String 
   
   <SoapAttribute(DataType:= "base64Binary")> _
   Public GroupNumber() As Byte

   <SoapAttribute(DataType:= "date", _
   AttributeName:= "CreationDate")> _
   Public Today As DateTime 
   <SoapElement(DataType:= "nonNegativeInteger", _
   ElementName:= "PosInt")> _
   Public PostitiveInt As String 
   ' This is ignored when serialized unless it's overridden.
   <SoapIgnore> _ 
   Public IgnoreThis As Boolean 
   
   Public Grouptype As GroupType 

   Public MyVehicle As Vehicle 

   '  The SoapInclude allows the method to return a Car.
   <SoapInclude(GetType(Car))> _
   Public Function myCar(licNumber As String ) As Vehicle 
      Dim v As Vehicle 
      if licNumber = "" Then
         v = New Car()
         v.licenseNumber = "!!!!!!"
      else  
       v = New Car()
       v.licenseNumber = licNumber
      End If
      
      return v
   End Function
End Class
  
' SoapInclude allows Vehicle to accept Car type.
<SoapInclude(GetType(Car))> _
Public MustInherit  class Vehicle
   Public licenseNumber As String 
   Public makeDate As DateTime 
End Class

Public Class Car
   Inherits Vehicle

End Class

Public enum GroupType
   ' These enums can be overridden.
   <SoapEnum("Small")> _
   A
   <SoapEnum("Large")> _ 
   B
End Enum
 
Public Class Run

   Shared Sub Main()
      Dim test As Run = New Run()
      test.SerializeOriginal("SoapOriginal.xml")
      test.SerializeOverride("SoapOverrides.xml")
      test.DeserializeOriginal("SoapOriginal.xml")
      test.DeserializeOverride("SoapOverrides.xml")
   End SUb
   
   Public Sub SerializeOriginal(filename As String)

      ' Create an instance of the XmlSerializer class.
      Dim myMapping As XmlTypeMapping = _
      (New SoapReflectionImporter().ImportTypeMapping _
      (GetType(Group)))
      Dim mySerializer As XmlSerializer =  _
      New XmlSerializer(myMapping)
      
      Dim myGroup As Group =MakeGroup()
      ' Writing the file requires a TextWriter.
      Dim writer As XmlTextWriter  = _
      New XmlTextWriter(filename, Encoding.UTF8)
      writer.Formatting = Formatting.Indented
      writer.WriteStartElement("wrapper")
      ' Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup)
      writer.WriteEndElement()
      writer.Close()
   End Sub

   Public Sub SerializeOverride(filename As String)
      ' Create an instance of the XmlSerializer class
      ' that overrides the serialization.
      Dim overRideSerializer As XmlSerializer = _
      CreateOverrideSerializer()
      Dim myGroup As Group =MakeGroup()
      ' Writing the file requires a TextWriter.
      Dim writer As XmlTextWriter  = _
      New XmlTextWriter(filename, Encoding.UTF8)
      writer.Formatting = Formatting.Indented
      writer.WriteStartElement("wrapper")
      ' Serialize the class, and close the TextWriter.
      overRideSerializer.Serialize(writer, myGroup)
      writer.WriteEndElement()
      writer.Close()
    End Sub

   private Function MakeGroup() As Group 
      ' Create an instance of the class that will be serialized.
      Dim myGroup As Group  = New Group()

      ' Set the object properties.
      myGroup.GroupName = ".NET"

      Dim hexByte()As Byte = new Byte(1){Convert.ToByte(100), _
      Convert.ToByte(50)}
      myGroup.GroupNumber = hexByte

      Dim myDate As DateTime  = new DateTime(2002,5,2)
      myGroup.Today = myDate

      myGroup.PostitiveInt = "10000"
    myGroup.IgnoreThis = true
    myGroup.Grouptype = GroupType.B
    Dim thisCar As Car 
    thisCar =CType(myGroup.myCar("1234566"), Car)
    myGroup.myVehicle=thisCar
      return myGroup
   End Function   	

   Public Sub DeserializeOriginal(filename As String)
      ' Create an instance of the XmlSerializer class.
      Dim myMapping As XmlTypeMapping = _
      (New SoapReflectionImporter().ImportTypeMapping _
      (GetType(Group)))
      Dim mySerializer As XmlSerializer =  _
      New XmlSerializer(myMapping)

      ' Reading the file requires an  XmlTextReader.
      Dim reader As XmlTextReader = _
      New XmlTextReader(filename)
      reader.ReadStartElement("wrapper")

      ' Deserialize and cast the object.
      Dim myGroup As Group  = _
      CType(mySerializer.Deserialize(reader), Group)
      reader.ReadEndElement()
      reader.Close()
   End Sub

   Public Sub DeserializeOverride(filename As String)
      ' Create an instance of the XmlSerializer class.
      Dim overRideSerializer As XmlSerializer  = _
      CreateOverrideSerializer()

      ' Reading the file requires an  XmlTextReader.
      Dim reader As XmlTextReader = _
      New XmlTextReader(filename)
      reader.ReadStartElement("wrapper")

      ' Deserialize and cast the object.
      Dim myGroup As Group = _
      CType(overRideSerializer.Deserialize(reader), Group)
      reader.ReadEndElement()
      reader.Close()
      ReadGroup(myGroup)
   End Sub

   private Sub ReadGroup(myGroup As Group)
      Console.WriteLine(myGroup.GroupName)
      Console.WriteLine(myGroup.GroupNumber(0))
      Console.WriteLine(myGroup.GroupNumber(1))
      Console.WriteLine(myGroup.Today)
      Console.WriteLine(myGroup.PostitiveInt)
      Console.WriteLine(myGroup.IgnoreThis)
      Console.WriteLine()
   End Sub
   
   Private Function CreateOverrideSerializer() As XmlSerializer
      Dim soapOver As SoapAttributeOverrides = New SoapAttributeOverrides()
      Dim soapAtts As SoapAttributes = New SoapAttributes()

      Dim mySoapElement As SoapElementAttribute = New SoapElementAttribute()
      mySoapElement.ElementName = "xxxx"
      soapAtts.SoapElement = mySoapElement
      soapOver.Add(GetType(Group), "PostitiveInt", soapAtts)

      ' Override the IgnoreThis property.
      Dim myIgnore As SoapIgnoreAttribute  = new SoapIgnoreAttribute()
      soapAtts = New SoapAttributes()
      soapAtts.SoapIgnore = false
      soapOver.Add(GetType(Group), "IgnoreThis", soapAtts)

      ' Override the GroupType enumeration.
      soapAtts = New SoapAttributes()
      Dim xSoapEnum As SoapEnumAttribute = new SoapEnumAttribute()
      xSoapEnum.Name = "Over1000"
      soapAtts.SoapEnum = xSoapEnum
      ' Add the SoapAttributes to the SoapOverrides object.
      soapOver.Add(GetType(GroupType), "A", soapAtts)

      ' Create second enumeration and add it.
      soapAtts = New SoapAttributes()
      xSoapEnum = New SoapEnumAttribute()
      xSoapEnum.Name = "ZeroTo1000"
      soapAtts.SoapEnum = xSoapEnum
      soapOver.Add(GetType(GroupType), "B", soapAtts)

      ' Override the Group type.
      soapAtts = New SoapAttributes()
      Dim soapType As SoapTypeAttribute = New SoapTypeAttribute()
      soapType.TypeName = "Team"
      soapAtts.SoapType = soapType
      soapOver.Add(GetType(Group),soapAtts)
    
      Dim myMapping As XmlTypeMapping = (New SoapReflectionImporter( _
      soapOver)).ImportTypeMapping(GetType(Group))
    
       Dim ser As XmlSerializer = new XmlSerializer(myMapping)
      return ser
   End Function
End Class

Opmerkingen

Deze constructor wordt gebruikt om een XmlSerializer object te maken wanneer u een object serialiseert in een SOAP-bericht. Als u de GEGENEREERDe SOAP-berichten wilt beheren, gebruikt u de speciale kenmerken (beginnend met het woord 'Soap') die in de System.Xml.Serialization naamruimte zijn gevonden.

Zie ook

• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, System::String ^ defaultNamespace);

public XmlSerializer(Type type, string defaultNamespace);

new System.Xml.Serialization.XmlSerializer : Type * string -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, defaultNamespace As String)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een XmlSerializer object met de naam Widgetgeserialiseerd. In het voorbeeld worden verschillende eigenschappen van het object ingesteld voordat de Serialize methode wordt aangeroepen.

private void SerializeObject(string filename) {
    XmlSerializer serializer = new XmlSerializer
        (typeof(OrderedItem), "http://www.cpandl.com");

    // Create an instance of the class to be serialized.
    OrderedItem i = new OrderedItem();

    // Insert code to set property values.

    // Writing the document requires a TextWriter.
    TextWriter writer = new StreamWriter(filename);
    // Serialize the object, and close the TextWriter
    serializer.Serialize(writer, i);
    writer.Close();
}

private void DeserializeObject(string filename) {
    XmlSerializer serializer = new XmlSerializer
        (typeof(OrderedItem), "http://www.cpandl.com");
    // A FileStream is needed to read the XML document.
    FileStream fs = new FileStream(filename, FileMode.Open);

    // Declare an object variable of the type to be deserialized.
    OrderedItem i;

    // Deserialize the object.
    i = (OrderedItem) serializer.Deserialize(fs);

    // Insert code to use the properties and methods of the object.
}

Private Sub SerializeObject(ByVal filename As String)
    Dim serializer As New XmlSerializer(GetType(OrderedItem), _
                                          "http://www.cpandl.com")
    
    ' Create an instance of the class to be serialized.
    Dim i As New OrderedItem()
    
    ' Insert code to set property values.
    ' Writing the document requires a TextWriter.
    Dim writer As New StreamWriter(filename)
    ' Serialize the object, and close the TextWriter.
    serializer.Serialize(writer, i)
    writer.Close()
End Sub


Private Sub DeserializeObject(ByVal filename As String)
    Dim serializer As New XmlSerializer(GetType(OrderedItem), _
                                          "http://www.cpandl.com")
    ' A FileStream is needed to read the XML document.
    Dim fs As New FileStream(filename, FileMode.Open)
    
    ' Declare an object variable of the type to be deserialized.
    Dim i As OrderedItem
    
    ' Deserialize the object.
    i = CType(serializer.Deserialize(fs), OrderedItem)
    ' Insert code to use the properties and methods of the object.
End Sub

Zie ook

• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, cli::array <Type ^> ^ extraTypes);

public XmlSerializer(Type type, Type[] extraTypes);

new System.Xml.Serialization.XmlSerializer : Type * Type[] -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, extraTypes As Type())

Parameters

Voorbeelden

In het volgende voorbeeld wordt een exemplaar van een klasse geserialiseerd dat een openbaar veld bevat dat een matrix met objecten retourneert. De extraTypes parameter van de XmlSerializer constructor geeft de typen van de objecten op die in de matrix kunnen worden geserialiseerd.

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;

// This defines the object that will be serialized.
public class Teacher
{
   public string Name;
   public Teacher(){}
   /* Note that the Info field returns an array of objects.
      Any object can be added to the array by adding the
      object type to the array passed to the extraTypes argument. */
   [XmlArray (ElementName = "ExtraInfo", IsNullable = true)]
   public object[] Info;
   public Phone PhoneInfo;
}

// This defines one of the extra types to be included.
public class Address
{
   public string City;

   public Address(){}
   public Address(string city)
   {
      City = city;
   }
}

// Another extra type to include.
public class Phone
{
   public string PhoneNumber;
   public Phone(){}
   public Phone(string phoneNumber)
   {
      PhoneNumber = phoneNumber;
   }
}

// Another type, derived from Phone
public class InternationalPhone:Phone
{
   public string CountryCode;

   public InternationalPhone(){}

   public InternationalPhone(string countryCode)
   {
      CountryCode = countryCode;
   }
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeObject("Teacher.xml");
      test.DeserializeObject("Teacher.xml");
   }

   private void SerializeObject(string filename)
   {
      // Writing the file requires a TextWriter.
      TextWriter myStreamWriter = new StreamWriter(filename);

      // Create a Type array.
      Type [] extraTypes= new Type[3];
      extraTypes[0] = typeof(Address);
      extraTypes[1] = typeof(Phone);
      extraTypes[2] = typeof(InternationalPhone);

      // Create the XmlSerializer instance.
      XmlSerializer mySerializer = new XmlSerializer
      (typeof(Teacher),extraTypes);

      Teacher teacher = new Teacher();
      teacher.Name = "Mike";
      // Add extra types to the Teacher object
      object [] info = new object[2];
      info[0] = new Address("Springville");
      info[1] = new Phone("555-0100");

      teacher.Info = info;

      teacher.PhoneInfo = new InternationalPhone("000");

      mySerializer.Serialize(myStreamWriter,teacher);
      myStreamWriter.Close();
   }

   private void DeserializeObject(string filename)
   {
      // Create a Type array.
      Type [] extraTypes= new Type[3];
      extraTypes[0] = typeof(Address);
      extraTypes[1] = typeof(Phone);
      extraTypes[2] = typeof(InternationalPhone);

      // Create the XmlSerializer instance.
      XmlSerializer mySerializer = new XmlSerializer
      (typeof(Teacher),extraTypes);

      // Reading a file requires a FileStream.
      FileStream fs = new FileStream(filename, FileMode.Open);
      Teacher teacher = (Teacher) mySerializer.Deserialize(fs);

      // Read the extra information.
      Address a = (Address)teacher.Info[0];
      Phone p = (Phone) teacher.Info[1];
      InternationalPhone Ip =
      (InternationalPhone) teacher.PhoneInfo;

      Console.WriteLine(teacher.Name);
      Console.WriteLine(a.City);
      Console.WriteLine(p.PhoneNumber);
      Console.WriteLine(Ip.CountryCode);
   }
}

Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization



' This defines the object that will be serialized.
Public Class Teacher
    Public Name As String
    
    Public Sub New()
    End Sub
    ' Note that the Info field returns an array of objects.
    ' Any object can be added to the array by adding the
    ' object type to the array passed to the extraTypes argument. 
    <XmlArray(ElementName := "ExtraInfo", IsNullable := True)> _
    Public Info() As Object
    Public PhoneInfo As Phone
End Class


' This defines one of the extra types to be included.
Public Class Address
    Public City As String
    
    Public Sub New()
    End Sub
    
    Public Sub New(city As String)
        me.City = city
    End Sub
End Class
 

' Another extra type to include.
Public Class Phone
    Public PhoneNumber As String
    
    Public Sub New()
    End Sub
    
    Public Sub New(phoneNumber As String)
        me.PhoneNumber = phoneNumber
    End Sub
End Class


' Another type, derived from Phone.
Public Class InternationalPhone
    Inherits Phone
    Public CountryCode As String
    
    
    Public Sub New()
    End Sub
     
    Public Sub New(countryCode As String)
        me.CountryCode = countryCode
    End Sub
End Class


Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("Teacher.xml")
        test.DeserializeObject("Teacher.xml")
    End Sub
    
    
    Private Sub SerializeObject(filename As String)
        ' Writing the file requires a TextWriter.
        Dim myStreamWriter As New StreamWriter(filename)
        
        ' Create a Type array.
        Dim extraTypes(2) As Type
        extraTypes(0) = GetType(Address)
        extraTypes(1) = GetType(Phone)
        extraTypes(2) = GetType(InternationalPhone)
        
        ' Create the XmlSerializer instance.
        Dim mySerializer As New XmlSerializer(GetType(Teacher), extraTypes)
        
        Dim teacher As New Teacher()
        teacher.Name = "Mike"
        ' Add extra types to the Teacher object.
        Dim info(1) As Object
        info(0) = New Address("Springville")
        info(1) = New Phone("555-0100")
        
        teacher.Info = info
        
        teacher.PhoneInfo = New InternationalPhone("000")
        
        mySerializer.Serialize(myStreamWriter, teacher)
        myStreamWriter.Close()
    End Sub
    
    
    Private Sub DeserializeObject(filename As String)
        ' Create a Type array.
        Dim extraTypes(2) As Type
        extraTypes(0) = GetType(Address)
        extraTypes(1) = GetType(Phone)
        extraTypes(2) = GetType(InternationalPhone)
        
        ' Create the XmlSerializer instance.
        Dim mySerializer As New XmlSerializer(GetType(Teacher), extraTypes)
        
        ' Reading a file requires a FileStream.
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim teacher As Teacher = CType(mySerializer.Deserialize(fs), Teacher)
        
        ' Read the extra information.
        Dim a As Address = CType(teacher.Info(0), Address)
        Dim p As Phone = CType(teacher.Info(1), Phone)
        Dim Ip As InternationalPhone = CType(teacher.PhoneInfo, InternationalPhone)
        
        Console.WriteLine(teacher.Name)
        Console.WriteLine(a.City)
        Console.WriteLine(p.PhoneNumber)
        Console.WriteLine(Ip.CountryCode)
    End Sub
End Class

Opmerkingen

Als een openbare eigenschap of veld standaard een object of matrix met objecten retourneert, worden de objecttypen automatisch geserialiseerd. Als een klasse echter een veld of eigenschap bevat die een matrix van het type Objectretourneert, kan elk object in die matrix worden ingevoegd. In dat geval moet de XmlSerializer instructie worden gegeven om alle mogelijke objecttypen te verwachten die in de Object matrix zijn ingevoegd. Gebruik hiervoor de extraTypes parameter om de extra objecttypen op te geven die moeten worden geserialiseerd of gedeserialiseerd.

U kunt de extraTypes parameter ook gebruiken om typen op te geven die zijn afgeleid van een basisklasse. Stel dat er een basisklasse met de naam Phone bestaat en dat een klasse met de naam InternationalPhone ervan is afgeleid. Gebruik de extraTypes parameter om ook het afgeleide type op te geven.

Zie ook

• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, System::Xml::Serialization::XmlAttributeOverrides ^ overrides);

public XmlSerializer(Type type, System.Xml.Serialization.XmlAttributeOverrides overrides);

new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlAttributeOverrides -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, overrides As XmlAttributeOverrides)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een exemplaar van een klasse geserialiseerd die is gedefinieerd in een DLL en om dit te doen, worden de openbare leden in het DLL-bestand overschreven.

// Beginning of HighSchool.dll
namespace HighSchool
{
   public class Student
   {
      public string Name;
      public int ID;
   }

   public class MyClass
   {
      public Student[] Students;
   }
}

namespace College
   {
   using System;
   using System.IO;
   using System.Xml;
   using System.Xml.Serialization;
   using HighSchool;

    public class Graduate:HighSchool.Student
    {
       public Graduate(){}
       // Add a new field named University.
       public string University;
    }

   public class Run
   {
      public static void Main()
      {
         Run test = new Run();
         test.WriteOverriddenAttributes("College.xml");
         test.ReadOverriddenAttributes("College.xml");
      }

      private void WriteOverriddenAttributes(string filename)
      {
         // Writing the file requires a TextWriter.
         TextWriter myStreamWriter = new StreamWriter(filename);
         // Create an XMLAttributeOverrides class.
         XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
         // Create the XmlAttributes class.
         XmlAttributes attrs = new XmlAttributes();

         /* Override the Student class. "Alumni" is the name
         of the overriding element in the XML output. */
         XmlElementAttribute attr =
         new XmlElementAttribute("Alumni", typeof(Graduate));

         /* Add the XmlElementAttribute to the collection of
         elements in the XmlAttributes object. */
         attrs.XmlElements.Add(attr);

         /* Add the XmlAttributes to the XmlAttributeOverrides.
         "Students" is the name being overridden. */
         attrOverrides.Add(typeof(HighSchool.MyClass),
         "Students", attrs);

         // Create the XmlSerializer.
         XmlSerializer mySerializer = new XmlSerializer
         (typeof(HighSchool.MyClass), attrOverrides);

         MyClass myClass = new MyClass();

         Graduate g1 = new Graduate();
         g1.Name = "Jackie";
         g1.ID = 1;
         g1.University = "Alma Mater";

         Graduate g2 = new Graduate();
         g2.Name = "Megan";
         g2.ID = 2;
         g2.University = "CM";

         Student[] myArray = {g1,g2};
         myClass.Students = myArray;

         mySerializer.Serialize(myStreamWriter, myClass);
         myStreamWriter.Close();
      }

      private void ReadOverriddenAttributes(string filename)
      {
         /* The majority of the code here is the same as that in the
         WriteOverriddenAttributes method. Because the XML being read
         doesn't conform to the schema defined by the DLL, the
         XMLAttributesOverrides must be used to create an
         XmlSerializer instance to read the XML document.*/

         XmlAttributeOverrides attrOverrides = new
         XmlAttributeOverrides();
         XmlAttributes attrs = new XmlAttributes();
         XmlElementAttribute attr =
         new XmlElementAttribute("Alumni", typeof(Graduate));
         attrs.XmlElements.Add(attr);
         attrOverrides.Add(typeof(HighSchool.MyClass),
         "Students", attrs);

         XmlSerializer readSerializer = new XmlSerializer
         (typeof(HighSchool.MyClass), attrOverrides);

         // To read the file, a FileStream object is required.
         FileStream fs = new FileStream(filename, FileMode.Open);

         MyClass myClass;

         myClass = (MyClass) readSerializer.Deserialize(fs);

         /* Here is the difference between reading and writing an
         XML document: You must declare an object of the derived
         type (Graduate) and cast the Student instance to it.*/
         Graduate g;

         foreach(Graduate grad in myClass.Students)
         {
            g = (Graduate) grad;
            Console.Write(g.Name + "\t");
            Console.Write(g.ID + "\t");
            Console.Write(g.University + "\n");
         }
      }
   }
}

' Beginning of HighSchool.dll
Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization
Imports HighSchool

Namespace HighSchool
    
    Public Class Student
        Public Name As String
        Public ID As Integer
    End Class
    
    
    Public Class MyClass1
        Public Students() As Student
    End Class
End Namespace 'HighSchool

Namespace College
    Public Class Graduate
        Inherits HighSchool.Student
        
        Public Sub New()
        End Sub
        Public University As String
    End Class
    
    
    
    Public Class Run
        
        Public Shared Sub Main()
            Dim test As New Run()
            test.WriteOverriddenAttributes("College.xml")
            test.ReadOverriddenAttributes("College.xml")
        End Sub
        
        
        Private Sub WriteOverriddenAttributes(filename As String)
            ' Writing the file requires a TextWriter.
            Dim myStreamWriter As New StreamWriter(filename)
            ' Create an XMLAttributeOverrides class.
            Dim attrOverrides As New XmlAttributeOverrides()
            ' Create the XmlAttributes class.
            Dim attrs As New XmlAttributes()
            
            ' Override the Student class. "Alumni" is the name
            ' of the overriding element in the XML output. 
            Dim attr As New XmlElementAttribute("Alumni", GetType(Graduate))
            
            ' Add the XmlElementAttribute to the collection of
            ' elements in the XmlAttributes object. 
            attrs.XmlElements.Add(attr)
            
            ' Add the XmlAttributes to the XmlAttributeOverrides. 
            ' "Students" is the name being overridden. 
            attrOverrides.Add(GetType(HighSchool.MyClass1), "Students", attrs)
            
            ' Create the XmlSerializer. 
            Dim mySerializer As New XmlSerializer(GetType(HighSchool.MyClass1), attrOverrides)
            
            Dim oMyClass As New MyClass1()
            
            Dim g1 As New Graduate()
            g1.Name = "Jackie"
            g1.ID = 1
            g1.University = "Alma Mater"
            
            Dim g2 As New Graduate()
            g2.Name = "Megan"
            g2.ID = 2
            g2.University = "CM"
            
            Dim myArray As Student() =  {g1, g2}
            oMyClass.Students = myArray
            
            mySerializer.Serialize(myStreamWriter, oMyClass)
            myStreamWriter.Close()
        End Sub
        
        
        Private Sub ReadOverriddenAttributes(filename As String)
            ' The majority of the code here is the same as that in the
            ' WriteOverriddenAttributes method. Because the XML being read
            ' doesn't conform to the schema defined by the DLL, the
            ' XMLAttributesOverrides must be used to create an
            ' XmlSerializer instance to read the XML document.
            
            Dim attrOverrides As New XmlAttributeOverrides()
            Dim attrs As New XmlAttributes()
            Dim attr As New XmlElementAttribute("Alumni", GetType(Graduate))
            attrs.XmlElements.Add(attr)
            attrOverrides.Add(GetType(HighSchool.MyClass1), "Students", attrs)
            
            Dim readSerializer As New XmlSerializer(GetType(HighSchool.MyClass1), attrOverrides)
            
            ' To read the file, a FileStream object is required. 
            Dim fs As New FileStream(filename, FileMode.Open)
            
            Dim oMyClass As MyClass1
            
            oMyClass = CType(readSerializer.Deserialize(fs), MyClass1)
            
            ' Here is the difference between reading and writing an
            ' XML document: You must declare an object of the derived
            ' type (Graduate) and cast the Student instance to it.
            Dim g As Graduate
            
            Dim grad As Graduate
            For Each grad In  oMyClass.Students
                g = CType(grad, Graduate)
                Console.Write((g.Name & ControlChars.Tab))
                Console.Write((g.ID.ToString & ControlChars.Tab))
                Console.Write((g.University & ControlChars.Cr))
            Next grad
        End Sub
    End Class
End Namespace 'College

Opmerkingen

De overrides parameter kan worden gebruikt om te bepalen hoe velden en eigenschappen in XML worden gecodeerd. Deze instellingen overschrijven alle kenmerken die al bestaan op de objecten. Dit kan handig zijn wanneer de broncode niet kan worden gewijzigd of als er meerdere coderingen vereist zijn voor dezelfde klassen.

Zie ook

• XmlAttributeOverrides
• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, System::Xml::Serialization::XmlRootAttribute ^ root);

public XmlSerializer(Type type, System.Xml.Serialization.XmlRootAttribute root);

new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlRootAttribute -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, root As XmlRootAttribute)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een XmlSerializer constructie gemaakt die gebruikmaakt van een XmlRootAttribute die verschillende eigenschappen van het XML-hoofdelement bevat, zoals de naamruimte en elementnaam.

private void SerializeObject(string filename) {
    // Create an XmlRootAttribute, and set its properties.
    XmlRootAttribute xRoot = new XmlRootAttribute();
    xRoot.ElementName = "CustomRoot";
    xRoot.Namespace = "http://www.cpandl.com";
    xRoot.IsNullable = true;

    // Construct the XmlSerializer with the XmlRootAttribute.
    XmlSerializer serializer = new XmlSerializer
        (typeof(OrderedItem),xRoot);

    // Create an instance of the object to serialize.
    OrderedItem i = new OrderedItem();
    // Insert code to set properties of the ordered item.

    // Writing the document requires a TextWriter.
    TextWriter writer = new StreamWriter(filename);

    serializer.Serialize(writer, i);
    writer.Close();
}

private void DeserializeObject(string filename) {
    // Create an XmlRootAttribute, and set its properties.
    XmlRootAttribute xRoot = new XmlRootAttribute();
    xRoot.ElementName = "CustomRoot";
    xRoot.Namespace = "http://www.cpandl.com";
    xRoot.IsNullable = true;

    XmlSerializer serializer = new XmlSerializer
        (typeof(OrderedItem),xRoot);

    // A FileStream is needed to read the XML document.
    FileStream fs = new FileStream(filename, FileMode.Open);
    // Deserialize the object.
    OrderedItem i = (OrderedItem) serializer.Deserialize(fs);
    // Insert code to use the object's properties and methods.
}

Private Sub SerializeObject(ByVal filename As String)
    ' Create an XmlRootAttribute, and set its properties.
    Dim xRoot As New XmlRootAttribute()
    xRoot.ElementName = "CustomRoot"
    xRoot.Namespace = "http://www.cpandl.com"
    xRoot.IsNullable = True
    
    ' Construct the XmlSerializer with the XmlRootAttribute.
    Dim serializer As New XmlSerializer(GetType(OrderedItem), xRoot)
    
    ' Create an instance of the object to serialize.
    Dim i As New OrderedItem()
    ' Insert code to set properties of the ordered item.
    ' Writing the document requires a TextWriter.
    Dim writer As New StreamWriter(filename)
    
    serializer.Serialize(writer, i)
    writer.Close()
End Sub
    
Private Sub DeserializeObject(ByVal filename As String)
    ' Create an XmlRootAttribute, and set its properties.
    Dim xRoot As New XmlRootAttribute()
    xRoot.ElementName = "CustomRoot"
    xRoot.Namespace = "http://www.cpandl.com"
    xRoot.IsNullable = True
    
    Dim serializer As New XmlSerializer(GetType(OrderedItem), xRoot)
    
    ' A FileStream is needed to read the XML document.
    Dim fs As New FileStream(filename, FileMode.Open)
    ' Deserialize the object.
    Dim i As OrderedItem = CType(serializer.Deserialize(fs), OrderedItem)
    ' Insert code to use the object's properties and methods.
End Sub

Opmerkingen

Het hoofdelement van een XML-document bevat alle andere elementen. Standaard wordt het object dat door de type parameter is opgegeven, geserialiseerd als het hoofdelement. Eigenschappen, zoals de naam van het XML-element van het hoofdelement, worden uit het type object gehaald. Met de parameter kunt u echter root de informatie van het standaardobject vervangen door een XmlRootAttribute; het object stelt u in staat om een andere naamruimte, elementnaam enzovoort in te stellen.

Zie ook

• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, System::Xml::Serialization::XmlAttributeOverrides ^ overrides, cli::array <Type ^> ^ extraTypes, System::Xml::Serialization::XmlRootAttribute ^ root, System::String ^ defaultNamespace);

public XmlSerializer(Type type, System.Xml.Serialization.XmlAttributeOverrides overrides, Type[] extraTypes, System.Xml.Serialization.XmlRootAttribute root, string defaultNamespace);

new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlAttributeOverrides * Type[] * System.Xml.Serialization.XmlRootAttribute * string -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, overrides As XmlAttributeOverrides, extraTypes As Type(), root As XmlRootAttribute, defaultNamespace As String)

Parameters

Voorbeelden

In het volgende voorbeeld wordt een exemplaar van een klasse geserialiseerd dat is gedefinieerd in een DLL en om dit te doen, worden de openbare leden in de klasse overschreven. In het voorbeeld wordt ook een matrix met extra typen opgegeven, de standaardnaamruimte voor alle XML-elementen en de klasse die moet worden gebruikt voor informatie over het XML-hoofdelement. In het voorbeeld wordt ervan uitgegaan dat de code aan het begin is gecompileerd in een DLL-bestand met de naam HighSchool.

// Beginning of the HighSchool.dll

namespace HighSchool
{
   public class Student
   {
      public string Name;
      public int ID;
   }

   public class MyClass
   {
      public Student[] Students;
   }
}

namespace College
   {
   using System;
   using System.IO;
   using System.Xml;
   using System.Xml.Serialization;
   using HighSchool;

    public class Graduate:HighSchool.Student
    {
       public Graduate(){}
       // Add a new field named University.
       public string University;
       // Use extra types to use this field.
       public object[]Info;
    }

    public class Address
    {
       public string City;
    }

    public class Phone
    {
       public string Number;
    }

   public class Run
   {
      public static void Main()
      {
         Run test = new Run();
         test.WriteOverriddenAttributes("College.xml");
         test.ReadOverriddenAttributes("College.xml");
      }

      private void WriteOverriddenAttributes(string filename)
      {
         // Writing the file requires a TextWriter.
         TextWriter myStreamWriter = new StreamWriter(filename);
         // Create an XMLAttributeOverrides class.
         XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
         // Create the XmlAttributes class.
         XmlAttributes attrs = new XmlAttributes();
         /* Override the Student class. "Alumni" is the name
         of the overriding element in the XML output. */

         XmlElementAttribute attr =
         new XmlElementAttribute("Alumni", typeof(Graduate));
         /* Add the XmlElementAttribute to the collection of
         elements in the XmlAttributes object. */
         attrs.XmlElements.Add(attr);
         /* Add the XmlAttributes to the XmlAttributeOverrides.
         "Students" is the name being overridden. */
         attrOverrides.Add(typeof(HighSchool.MyClass),
         "Students", attrs);

         // Create array of extra types.
         Type [] extraTypes = new Type[2];
         extraTypes[0]=typeof(Address);
         extraTypes[1]=typeof(Phone);

         // Create an XmlRootAttribute.
         XmlRootAttribute root = new XmlRootAttribute("Graduates");

         /* Create the XmlSerializer with the
         XmlAttributeOverrides object. */
         XmlSerializer mySerializer = new XmlSerializer
         (typeof(HighSchool.MyClass), attrOverrides, extraTypes,
         root, "http://www.microsoft.com");

         MyClass myClass= new MyClass();

         Graduate g1 = new Graduate();
         g1.Name = "Jacki";
         g1.ID = 1;
         g1.University = "Alma";

         Graduate g2 = new Graduate();
         g2.Name = "Megan";
         g2.ID = 2;
         g2.University = "CM";

         Student[] myArray = {g1,g2};

         myClass.Students = myArray;

         // Create extra information.
         Address a1 = new Address();
         a1.City = "Ionia";
         Address a2 = new Address();
         a2.City = "Stamford";
         Phone p1 = new Phone();
         p1.Number = "555-0101";
         Phone p2 = new Phone();
         p2.Number = "555-0100";

         Object[]o1 = new Object[2]{a1, p1};
         Object[]o2 = new Object[2]{a2,p2};

         g1.Info = o1;
         g2.Info = o2;
         mySerializer.Serialize(myStreamWriter,myClass);
         myStreamWriter.Close();
      }

      private void ReadOverriddenAttributes(string filename)
      {
         /* The majority of the code here is the same as that in the
         WriteOverriddenAttributes method. Because the XML being read
         doesn't conform to the schema defined by the DLL, the
         XMLAttributesOverrides must be used to create an
         XmlSerializer instance to read the XML document.*/

         XmlAttributeOverrides attrOverrides = new
         XmlAttributeOverrides();
         XmlAttributes attrs = new XmlAttributes();
         XmlElementAttribute attr =
         new XmlElementAttribute("Alumni", typeof(Graduate));
         attrs.XmlElements.Add(attr);
         attrOverrides.Add(typeof(HighSchool.MyClass),
         "Students", attrs);

         Type [] extraTypes = new Type[2];
         extraTypes[0] = typeof(Address);
         extraTypes[1] = typeof(Phone);

         XmlRootAttribute root = new XmlRootAttribute("Graduates");

         XmlSerializer readSerializer = new XmlSerializer
         (typeof(HighSchool.MyClass), attrOverrides, extraTypes,
         root, "http://www.microsoft.com");

         // A FileStream object is required to read the file.
         FileStream fs = new FileStream(filename, FileMode.Open);

         MyClass myClass;
         myClass = (MyClass) readSerializer.Deserialize(fs);

         /* Here is the difference between reading and writing an
         XML document: You must declare an object of the derived
         type (Graduate) and cast the Student instance to it.*/
         Graduate g;
         Address a;
         Phone p;
         foreach(Graduate grad in myClass.Students)
         {
            g = (Graduate) grad;
            Console.Write(g.Name + "\t");
            Console.Write(g.ID + "\t");
            Console.Write(g.University + "\n");
            a = (Address) g.Info[0];
            Console.WriteLine(a.City);
            p = (Phone) g.Info[1];
            Console.WriteLine(p.Number);
         }
      }
   }
}

'Beginning of the HighSchool.dll 
Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization

' Imports HighSchool

Namespace HighSchool

    Public Class Student
        Public Name As String
        Public ID As Integer
    End Class


    Public Class ClassRoom
        Public Students() As Student
    End Class
End Namespace 'HighSchool

Namespace College
    Public Class Graduate
        Inherits HighSchool.Student

        Public Sub New()
        End Sub
        ' Add a new field named University.
        Public University As String
        ' Use extra types to use this field.
        Public Info() As Object
    End Class


    Public Class Address
        Public City As String
    End Class


    Public Class Phone
        Public Number As String
    End Class


    Public Class Run

        Public Shared Sub Main()
            Dim test As New Run()
            test.WriteOverriddenAttributes("College.xml")
            test.ReadOverriddenAttributes("College.xml")
        End Sub


        Private Sub WriteOverriddenAttributes(ByVal filename As String)
            ' Writing the file requires a TextWriter.
            Dim myStreamWriter As New StreamWriter(filename)
            ' Create an XMLAttributeOverrides class.
            Dim attrOverrides As New XmlAttributeOverrides()
            ' Create the XmlAttributes class.
            Dim attrs As New XmlAttributes()
            ' Override the Student class. "Alumni" is the name
            ' of the overriding element in the XML output. 

            Dim attr As New XmlElementAttribute("Alumni", GetType(Graduate))
            ' Add the XmlElementAttribute to the collection of
            ' elements in the XmlAttributes object. 
            attrs.XmlElements.Add(attr)
            ' Add the XmlAttributes to the XmlAttributeOverrides.
            ' "Students" is the name being overridden. 
            attrOverrides.Add(GetType(HighSchool.ClassRoom), "Students", attrs)

            ' Create array of extra types.
            Dim extraTypes(1) As Type
            extraTypes(0) = GetType(Address)
            extraTypes(1) = GetType(Phone)

            ' Create an XmlRootAttribute.
            Dim root As New XmlRootAttribute("Graduates")

            ' Create the XmlSerializer with the
            ' XmlAttributeOverrides object. 
            Dim mySerializer As New XmlSerializer(GetType(HighSchool.ClassRoom), _
                attrOverrides, extraTypes, root, "http://www.microsoft.com")

            Dim oMyClass As New HighSchool.ClassRoom()

            Dim g1 As New Graduate()
            g1.Name = "Jacki"
            g1.ID = 1
            g1.University = "Alma"

            Dim g2 As New Graduate()
            g2.Name = "Megan"
            g2.ID = 2
            g2.University = "CM"

            Dim myArray As HighSchool.Student() = {g1, g2}

            oMyClass.Students = myArray

            ' Create extra information.
            Dim a1 As New Address()
            a1.City = "Ionia"
            Dim a2 As New Address()
            a2.City = "Stamford"
            Dim p1 As New Phone()
            p1.Number = "555-0101"
            Dim p2 As New Phone()
            p2.Number = "555-0100"

            Dim o1() As Object = {a1, p1}
            Dim o2() As Object = {a2, p2}

            g1.Info = o1
            g2.Info = o2
            mySerializer.Serialize(myStreamWriter, oMyClass)
            myStreamWriter.Close()
        End Sub


        Private Sub ReadOverriddenAttributes(ByVal filename As String)
            ' The majority of the code here is the same as that in the
            ' WriteOverriddenAttributes method. Because the XML being read
            ' doesn't conform to the schema defined by the DLL, the
            ' XMLAttributesOverrides must be used to create an
            ' XmlSerializer instance to read the XML document.

            Dim attrOverrides As New XmlAttributeOverrides()
            Dim attrs As New XmlAttributes()
            Dim attr As New XmlElementAttribute("Alumni", GetType(Graduate))
            attrs.XmlElements.Add(attr)
            attrOverrides.Add(GetType(HighSchool.ClassRoom), "Students", attrs)

            Dim extraTypes(1) As Type
            extraTypes(0) = GetType(Address)
            extraTypes(1) = GetType(Phone)

            Dim root As New XmlRootAttribute("Graduates")

            Dim readSerializer As New XmlSerializer(GetType(HighSchool.ClassRoom), _
                attrOverrides, extraTypes, root, "http://www.microsoft.com")

            ' A FileStream object is required to read the file. 
            Dim fs As New FileStream(filename, FileMode.Open)

            Dim oMyClass As HighSchool.ClassRoom
            oMyClass = CType(readSerializer.Deserialize(fs), HighSchool.ClassRoom)

            ' Here is the difference between reading and writing an
            ' XML document: You must declare an object of the derived
            ' type (Graduate) and cast the Student instance to it.
            Dim g As Graduate
            Dim a As Address
            Dim p As Phone
            Dim grad As Graduate
            For Each grad In oMyClass.Students
                g = CType(grad, Graduate)
                Console.Write((g.Name & ControlChars.Tab))
                Console.Write((g.ID & ControlChars.Tab))
                Console.Write((g.University & ControlChars.Cr))
                a = CType(g.Info(0), Address)
                Console.WriteLine(a.City)
                p = CType(g.Info(1), Phone)
                Console.WriteLine(p.Number)
            Next grad
        End Sub
    End Class
End Namespace 'College

Opmerkingen

Met overrides de parameter kunt u een XmlSerializer klasse maken die het gedrag van een basisklasse uitbreidt of overschrijft. Als u bijvoorbeeld een DLL hebt, is het mogelijk om een klasse te maken die een klasse over neemt of uitbreidt die deel uitmaakt van het DLL-bestand. Als u een dergelijke klasse wilt serialiseren, moet u een exemplaar van de klasse gebruiken bij het XmlAttributeOverrides maken van de XmlSerializerklasse. Zie XmlAttributeOverrides voor meer informatie.

Als een openbare eigenschap of veld standaard een object of matrix met objecten retourneert, worden de objecttypen automatisch geserialiseerd. Als een klasse echter een veld of eigenschap bevat die een matrix van het type Objectretourneert, kan elk object in die matrix worden ingevoegd. In dat geval moet de XmlSerializer instructie worden gegeven om alle mogelijke objecttypen te verwachten die in de Object matrix zijn ingevoegd. Gebruik hiervoor de extraTypes parameter om de extra objecttypen op te geven die moeten worden geserialiseerd of gedeserialiseerd.

Het hoofdelement van een XML-document bevat alle andere elementen. Standaard wordt het object dat door de type parameter is opgegeven, geserialiseerd als het hoofdelement. Eigenschappen, zoals de naam van het XML-element van het hoofdelement, worden uit het type object gehaald. Met de parameter kunt u echter root de informatie van het standaardobject vervangen door een XmlRootAttribute; het object stelt u in staat om een andere naamruimte, elementnaam enzovoort in te stellen.

Gebruik de defaultName parameter om de standaardnaamruimte op te geven van alle XML-elementen die door de XmlSerializerparameter worden gegenereerd.

Zie ook

• XmlAttributeOverrides
• XmlRootAttribute
• XmlAttributes
• Inleiding tot XML-serialisatie
• Procedure: Geef een alternatieve elementnaam op voor een XML-stream
• XML-serialisatie beheren met behulp van kenmerken
• Voorbeelden van XML-serialisatie
• Xml Schema Definition Tool (Xsd.exe)

public:
 XmlSerializer(Type ^ type, System::Xml::Serialization::XmlAttributeOverrides ^ overrides, cli::array <Type ^> ^ extraTypes, System::Xml::Serialization::XmlRootAttribute ^ root, System::String ^ defaultNamespace, System::String ^ location);

public XmlSerializer(Type type, System.Xml.Serialization.XmlAttributeOverrides overrides, Type[] extraTypes, System.Xml.Serialization.XmlRootAttribute root, string defaultNamespace, string location);

new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlAttributeOverrides * Type[] * System.Xml.Serialization.XmlRootAttribute * string * string -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, overrides As XmlAttributeOverrides, extraTypes As Type(), root As XmlRootAttribute, defaultNamespace As String, location As String)

Parameters

public:
 XmlSerializer(Type ^ type, System::Xml::Serialization::XmlAttributeOverrides ^ overrides, cli::array <Type ^> ^ extraTypes, System::Xml::Serialization::XmlRootAttribute ^ root, System::String ^ defaultNamespace, System::String ^ location, System::Security::Policy::Evidence ^ evidence);

public XmlSerializer(Type type, System.Xml.Serialization.XmlAttributeOverrides overrides, Type[] extraTypes, System.Xml.Serialization.XmlRootAttribute root, string defaultNamespace, string location, System.Security.Policy.Evidence evidence);

[System.Obsolete("This method is obsolete and will be removed in a future release of the .NET Framework. Please use a XmlSerializer constructor overload which does not take an Evidence parameter. See http://go2.microsoft.com/fwlink/?LinkId=131738 for more information.")]
public XmlSerializer(Type type, System.Xml.Serialization.XmlAttributeOverrides overrides, Type[] extraTypes, System.Xml.Serialization.XmlRootAttribute root, string defaultNamespace, string location, System.Security.Policy.Evidence evidence);

new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlAttributeOverrides * Type[] * System.Xml.Serialization.XmlRootAttribute * string * string * System.Security.Policy.Evidence -> System.Xml.Serialization.XmlSerializer

[<System.Obsolete("This method is obsolete and will be removed in a future release of the .NET Framework. Please use a XmlSerializer constructor overload which does not take an Evidence parameter. See http://go2.microsoft.com/fwlink/?LinkId=131738 for more information.")>]
new System.Xml.Serialization.XmlSerializer : Type * System.Xml.Serialization.XmlAttributeOverrides * Type[] * System.Xml.Serialization.XmlRootAttribute * string * string * System.Security.Policy.Evidence -> System.Xml.Serialization.XmlSerializer

Public Sub New (type As Type, overrides As XmlAttributeOverrides, extraTypes As Type(), root As XmlRootAttribute, defaultNamespace As String, location As String, evidence As Evidence)

Parameters

Kenmerken

ObsoleteAttribute

Opmerkingen

Hiermee kunt u de toegang tot een tijdelijke map nauwkeuriger beheren en code-injectie en exploitatie voorkomen. Als u deze methode wilt gebruiken, geeft u een locatie op en geeft u alleen toegang tot specifieke gebruikers. Beheerders kunnen beleidsregels instellen met bewijslijsten die overeenkomen met bewijsmateriaal voor machtigingen.