DataSet 类

定义

public ref class DataSet : System::ComponentModel::MarshalByValueComponent, System::ComponentModel::IListSource, System::ComponentModel::ISupportInitialize, System::ComponentModel::ISupportInitializeNotification, System::Runtime::Serialization::ISerializable, System::Xml::Serialization::IXmlSerializable

public ref class DataSet : System::ComponentModel::MarshalByValueComponent, System::ComponentModel::IListSource, System::ComponentModel::ISupportInitialize, System::Runtime::Serialization::ISerializable, System::Xml::Serialization::IXmlSerializable

public ref class DataSet : System::ComponentModel::MarshalByValueComponent, System::ComponentModel::IListSource, System::ComponentModel::ISupportInitializeNotification, System::Runtime::Serialization::ISerializable, System::Xml::Serialization::IXmlSerializable

[System.Diagnostics.CodeAnalysis.DynamicallyAccessedMembers(System.Diagnostics.CodeAnalysis.DynamicallyAccessedMemberTypes.NonPublicConstructors | System.Diagnostics.CodeAnalysis.DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)]
public class DataSet : System.ComponentModel.MarshalByValueComponent, System.ComponentModel.IListSource, System.ComponentModel.ISupportInitialize, System.ComponentModel.ISupportInitializeNotification, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable

public class DataSet : System.ComponentModel.MarshalByValueComponent, System.ComponentModel.IListSource, System.ComponentModel.ISupportInitialize, System.ComponentModel.ISupportInitializeNotification, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable

[System.Serializable]
public class DataSet : System.ComponentModel.MarshalByValueComponent, System.ComponentModel.IListSource, System.ComponentModel.ISupportInitialize, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable

[System.Serializable]
public class DataSet : System.ComponentModel.MarshalByValueComponent, System.ComponentModel.IListSource, System.ComponentModel.ISupportInitializeNotification, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable

public class DataSet : System.ComponentModel.MarshalByValueComponent, System.ComponentModel.IListSource, System.ComponentModel.ISupportInitializeNotification, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable

[<System.Diagnostics.CodeAnalysis.DynamicallyAccessedMembers(System.Diagnostics.CodeAnalysis.DynamicallyAccessedMemberTypes.NonPublicConstructors | System.Diagnostics.CodeAnalysis.DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)>]
type DataSet = class
    inherit MarshalByValueComponent
    interface IListSource
    interface ISupportInitialize
    interface ISupportInitializeNotification
    interface ISerializable
    interface IXmlSerializable

type DataSet = class
    inherit MarshalByValueComponent
    interface IListSource
    interface ISupportInitialize
    interface ISupportInitializeNotification
    interface ISerializable
    interface IXmlSerializable

[<System.Serializable>]
type DataSet = class
    inherit MarshalByValueComponent
    interface IListSource
    interface IXmlSerializable
    interface ISupportInitialize
    interface ISerializable

[<System.Serializable>]
type DataSet = class
    inherit MarshalByValueComponent
    interface IListSource
    interface IXmlSerializable
    interface ISupportInitializeNotification
    interface ISupportInitialize
    interface ISerializable

Public Class DataSet
Inherits MarshalByValueComponent
Implements IListSource, ISerializable, ISupportInitialize, ISupportInitializeNotification, IXmlSerializable

Public Class DataSet
Inherits MarshalByValueComponent
Implements IListSource, ISerializable, ISupportInitialize, IXmlSerializable

Public Class DataSet
Inherits MarshalByValueComponent
Implements IListSource, ISerializable, ISupportInitializeNotification, IXmlSerializable

继承

Object

MarshalByValueComponent

DataSet

属性

DynamicallyAccessedMembersAttribute SerializableAttribute

实现

IListSource ISupportInitialize ISupportInitializeNotification ISerializable IXmlSerializable

示例

以下示例包含几种方法，这些方法组合、创建和填充了 DataSet 数据库中的一个。

using System;
using System.Data;
using System.Data.SqlClient;

namespace Microsoft.AdoNet.DataSetDemo
{
    class NorthwindDataSet
    {
        static void Main()
        {
            string connectionString = GetConnectionString();
            ConnectToData(connectionString);
        }

        private static void ConnectToData(string connectionString)
        {
            //Create a SqlConnection to the Northwind database.
            using (SqlConnection connection =
                       new SqlConnection(connectionString))
            {
                //Create a SqlDataAdapter for the Suppliers table.
                SqlDataAdapter adapter = new SqlDataAdapter();

                // A table mapping names the DataTable.
                adapter.TableMappings.Add("Table", "Suppliers");

                // Open the connection.
                connection.Open();
                Console.WriteLine("The SqlConnection is open.");

                // Create a SqlCommand to retrieve Suppliers data.
                SqlCommand command = new SqlCommand(
                    "SELECT SupplierID, CompanyName FROM dbo.Suppliers;",
                    connection);
                command.CommandType = CommandType.Text;

                // Set the SqlDataAdapter's SelectCommand.
                adapter.SelectCommand = command;

                // Fill the DataSet.
                DataSet dataSet = new DataSet("Suppliers");
                adapter.Fill(dataSet);

                // Create a second Adapter and Command to get
                // the Products table, a child table of Suppliers.
                SqlDataAdapter productsAdapter = new SqlDataAdapter();
                productsAdapter.TableMappings.Add("Table", "Products");

                SqlCommand productsCommand = new SqlCommand(
                    "SELECT ProductID, SupplierID FROM dbo.Products;",
                    connection);
                productsAdapter.SelectCommand = productsCommand;

                // Fill the DataSet.
                productsAdapter.Fill(dataSet);

                // Close the connection.
                connection.Close();
                Console.WriteLine("The SqlConnection is closed.");

                // Create a DataRelation to link the two tables
                // based on the SupplierID.
                DataColumn parentColumn =
                    dataSet.Tables["Suppliers"].Columns["SupplierID"];
                DataColumn childColumn =
                    dataSet.Tables["Products"].Columns["SupplierID"];
                DataRelation relation =
                    new System.Data.DataRelation("SuppliersProducts",
                    parentColumn, childColumn);
                dataSet.Relations.Add(relation);
                Console.WriteLine(
                    "The {0} DataRelation has been created.",
                    relation.RelationName);
            }
        }

        static private string GetConnectionString()
        {
            // To avoid storing the connection string in your code,
            // you can retrieve it from a configuration file.
            return "Data Source=(local);Initial Catalog=Northwind;"
                + "Integrated Security=SSPI";
        }
    }
}

Option Explicit On
Option Strict On

Imports System.Data
Imports system.Data.SqlClient

Public Class NorthwindDataSet

    Public Shared Sub Main()
        Dim connectionString As String = _
            GetConnectionString()
        ConnectToData(connectionString)
    End Sub

    Private Shared Sub ConnectToData( _
        ByVal connectionString As String)

        ' Create a SqlConnection to the Northwind database.
        Using connection As SqlConnection = New SqlConnection( _
           connectionString)

            ' Create a SqlDataAdapter for the Suppliers table.
            Dim suppliersAdapter As SqlDataAdapter = _
               New SqlDataAdapter()

            ' A table mapping names the DataTable.
            suppliersAdapter.TableMappings.Add("Table", "Suppliers")

            ' Open the connection.
            connection.Open()
            Console.WriteLine("The SqlConnection is open.")

            ' Create a SqlCommand to retrieve Suppliers data.
            Dim suppliersCommand As New SqlCommand( _
               "SELECT SupplierID, CompanyName FROM dbo.Suppliers;", _
               connection)
            suppliersCommand.CommandType = CommandType.Text

            ' Set the SqlDataAdapter's SelectCommand.
            suppliersAdapter.SelectCommand = suppliersCommand

            ' Fill the DataSet.
            Dim dataSet As New DataSet("Suppliers")
            suppliersAdapter.Fill(dataSet)

            ' Create a second SqlDataAdapter and SqlCommand to get
            ' the Products table, a child table of Suppliers. 
            Dim productsAdapter As New SqlDataAdapter()
            productsAdapter.TableMappings.Add("Table", "Products")

            Dim productsCommand As New SqlCommand( _
               "SELECT ProductID, SupplierID FROM dbo.Products;", _
               connection)
            productsAdapter.SelectCommand = productsCommand

            ' Fill the DataSet.
            productsAdapter.Fill(dataSet)

            ' Close the connection.
            connection.Close()
            Console.WriteLine("The SqlConnection is closed.")

            ' Create a DataRelation to link the two tables
            ' based on the SupplierID.
            Dim parentColumn As DataColumn = _
               dataSet.Tables("Suppliers").Columns("SupplierID")
            Dim childColumn As DataColumn = _
               dataSet.Tables("Products").Columns("SupplierID")
            Dim relation As New DataRelation("SuppliersProducts", _
               parentColumn, childColumn)
            dataSet.Relations.Add(relation)

            Console.WriteLine( _
               "The {0} DataRelation has been created.", _
               relation.RelationName)
        End Using

    End Sub

    Private Shared Function GetConnectionString() As String
        ' To avoid storing the connection string in your code,  
        ' you can retrieve it from a configuration file.
        Return "Data Source=(local);Initial Catalog=Northwind;" _
           & "Integrated Security=SSPI;"
    End Function
End Class

注解

该 DataSet 类是从数据源检索到的数据的内存中缓存，是 ADO.NET 体系结构的主要组成部分。 DataSet 由一组 DataTable 对象组成，你可以通过 DataRelation 对象将它们彼此关联。 您还可以在DataSet中通过使用UniqueConstraint和ForeignKeyConstraint对象来实施数据完整性。 有关使用 DataSet 对象的更多详细信息，请参阅 DataSets、DataTables 和 DataViews。

而 DataTable 对象包含数据， DataRelationCollection 则允许你通过表层次结构进行导航。 表格包含在 DataTableCollection 中，并通过 Tables 属性访问。 访问 DataTable 对象时，请注意它们是有条件的区分大小写的。 例如，如果一个 DataTable 名为“mydatatable”，另一个名为“Mydatatable”，则用于搜索其中一个表的字符串被认为区分大小写。 但是，如果“mydatatable”存在且“Mydatatable”不存在，则搜索字符串被视为不区分大小写。 有关使用 DataTable 对象的详细信息，请参阅 创建 DataTable。

DataSet 可以以 XML 文档的形式读取和写入数据和模式。 然后，可以在启用 XML 的任何平台上跨 HTTP 传输数据和架构，并由任何应用程序使用。 可以使用该方法将架构另存为 XML 架构 WriteXmlSchema ，并且可以使用该方法保存 WriteXml 架构和数据。 若要读取包含架构和数据的 XML 文档，请使用 ReadXml 该方法。

在典型的多层实现中，创建和刷新原始 DataSet数据的步骤依次是：

1. 使用 DataTable 构建 DataSet 中的每个 DataAdapter，并用来自数据源的数据对其进行填充。

2. 通过添加、更新或删除DataTable对象来更改各个DataRow对象中的数据。

3. 调用 GetChanges 方法以创建仅包含对数据的更改的第二个 DataSet。

4. 调用 Update 的 DataAdapter 方法，并将第二个 DataSet 作为参数传递。

5. 调用Merge方法，将第二个DataSet中的更改合并到第一个中。

6. 在AcceptChanges上调用DataSet 或者，调用 RejectChanges 以取消更改。

安全注意事项

有关 DataSet 和 DataTable 安全性的信息，请参阅 安全指南。

线程安全性

此类型对于多线程读取操作是安全的。 必须同步任何写入操作。

另请参阅

• 在 ADO 中使用数据集.NET