GridViewDeleteEventArgs.Values Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee haalt u een woordenlijst op van de naam/waardeparen van het niet-sleutelveld voor de rij die u wilt verwijderen.
public:
property System::Collections::Specialized::IOrderedDictionary ^ Values { System::Collections::Specialized::IOrderedDictionary ^ get(); };public System.Collections.Specialized.IOrderedDictionary Values { get; }member this.Values : System.Collections.Specialized.IOrderedDictionaryPublic ReadOnly Property Values As IOrderedDictionaryWaarde van eigenschap
Een IOrderedDictionary object dat de niet-sleutelveldnaam/waardeparen van de rij bevat die u wilt verwijderen.
Voorbeelden
In het volgende voorbeeld ziet u hoe u de Values eigenschap gebruikt om de waarden van de niet-sleutelvelden op te halen die door de rij moeten worden verwijderd. De waarden worden vervolgens naar een logboekbestand met verwijderde records geschreven.
<%@ Page language="C#" %>
<%@ import namespace="System.IO" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void CustomersGridView_RowDeleting(Object sender, GridViewDeleteEventArgs e)
{
// Record the delete operation in a log file.
// Create the log text.
String logText = "";
// Append the values of the key fields to the log text.
foreach (DictionaryEntry keyEntry in e.Keys)
{
logText += keyEntry.Key + "=" + keyEntry.Value + ";";
}
// Append the values of the non-key fields to the log text.
foreach (DictionaryEntry valueEntry in e.Values)
{
logText += valueEntry.Key + "=" + valueEntry.Value + ";";
}
// Display the log content.
LogTextLabel.Text = logText;
// Append the text to a log file.
try
{
StreamWriter sw;
sw = File.AppendText(Server.MapPath(null) + "\\deletelog.txt");
sw.WriteLine(logText);
sw.Flush();
sw.Close();
}
catch(UnauthorizedAccessException ex)
{
// You must provide read/write access to the file using ACLs.
LogErrorLabel.Text = "You do not have permission to write to the log.";
}
}
void CustomersGridView_RowDeleted(Object sender, GridViewDeletedEventArgs e)
{
if (e.Exception == null)
{
// The delete operation succeeded. Clear the message label.
Message.Text = "";
}
else
{
// The delete operation failed. Display an error message.
Message.Text = e.AffectedRows.ToString() + " rows deleted. " + e.Exception.Message;
e.ExceptionHandled = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewDeleteEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewDeleteEventArgs Keys and Values Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:label id="LogTextLabel"
forecolor="Red"
runat="server"/>
<br/>
<asp:label id="LogErrorLabel"
forecolor="Red"
runat="server"/>
<br/>
<asp:gridview id="CustomersGridView"
allowpaging="true"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogeneratedeletebutton="true"
datakeynames="CustomerID"
onrowdeleted="CustomersGridView_RowDeleted"
onrowdeleting="CustomersGridView_RowDeleting"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete from Customers where CustomerID = @CustomerID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
<%@ Page language="VB" %>
<%@ import namespace="System.IO" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub CustomersGridView_RowDeleting(ByVal sender As Object, ByVal e As GridViewDeleteEventArgs)
' Record the delete operation in a log file.
' Create the log text.
Dim logText As String = ""
' Append the values of the key fields to the log text.
Dim i As Integer
For i = 0 To e.Keys.Count - 1
logText &= e.Keys(i).ToString() & ";"
Next
' Append the values of the non-key fields to the log text.
For i = 0 To e.Values.Count - 1
If e.Values(i) IsNot Nothing Then
logText &= e.Values(i).ToString() & ";"
Else
logText &= "Nothing" & ";"
End If
Next
' Display the log content.
LogTextLabel.Text = logText
' Append the text to a log file.
Try
Dim sw As StreamWriter
sw = File.AppendText(Server.MapPath(Nothing) & "\deletelog.txt")
sw.WriteLine(logText)
sw.Flush()
sw.Close()
Catch ex As UnauthorizedAccessException
' You must provide read/write access to the file using ACLs.
LogErrorLabel.Text = "You do not have permission to write to the log."
End Try
End Sub
Sub CustomersGridView_RowDeleted(ByVal sender As Object, ByVal e As GridViewDeletedEventArgs)
If e.Exception Is Nothing Then
' The delete operation succeeded. Clear the message label.
Message.Text = ""
Else
' The delete operation failed. Display an error message.
Message.Text = e.AffectedRows.ToString() & " rows deleted. " & e.Exception.Message
e.ExceptionHandled = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewDeleteEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewDeleteEventArgs Keys and Values Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:label id="LogTextLabel"
forecolor="Red"
runat="server"/>
<br/>
<asp:label id="LogErrorLabel"
forecolor="Red"
runat="server"/>
<br/>
<asp:gridview id="CustomersGridView"
allowpaging="true"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogeneratedeletebutton="true"
datakeynames="CustomerID"
onrowdeleted="CustomersGridView_RowDeleted"
onrowdeleting="CustomersGridView_RowDeleting"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete from Customers where CustomerID = @CustomerID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Opmerkingen
De Values eigenschap wordt automatisch ingevuld met de naam/waardeparen van de niet-sleutelvelden voor de rij. Als u de veldnaam van een item wilt bepalen, gebruikt u de DictionaryEntry.Key eigenschap van een System.Collections.DictionaryEntry object in de Values woordenlijst. Gebruik de DictionaryEntry.Value eigenschap om de waarde van een vermelding te bepalen.
Note
Het primaire-sleutelveld of de primaire-sleutelvelden zijn niet opgenomen in deze woordenlijst. Gebruik de Keys eigenschap om toegang te krijgen tot de waarden van het primaire-sleutelveld of de primaire-sleutelvelden.
