SqlDataSourceCommandEventArgs SqlDataSourceCommandEventArgs SqlDataSourceCommandEventArgs SqlDataSourceCommandEventArgs Class

Definition

Stellt Daten für die Ereignisse Updating, Deleting und Inserting des SqlDataSource-Steuerelements bereit.Provides data for the Updating, Deleting and Inserting events of the SqlDataSource control.

public ref class SqlDataSourceCommandEventArgs : System::ComponentModel::CancelEventArgs
public class SqlDataSourceCommandEventArgs : System.ComponentModel.CancelEventArgs
type SqlDataSourceCommandEventArgs = class
    inherit CancelEventArgs
Public Class SqlDataSourceCommandEventArgs
Inherits CancelEventArgs
Vererbung
SqlDataSourceCommandEventArgsSqlDataSourceCommandEventArgsSqlDataSourceCommandEventArgsSqlDataSourceCommandEventArgs
Abgeleitet

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie Sie Daten anzeigen, die aus einer Microsoft SQL Server DropDownList -Datenbank in einem-Steuerelement abgerufen TextBox wurden, und den Datensatz mithilfe eines-Steuer Elements aktualisierenThe following code example demonstrates how to display data retrieved from a Microsoft SQL Server database in a DropDownList control, and update the record using a TextBox control. Das Beispiel zeigt, wie Sie mithilfe eines DbTransaction -Objekts einen Transaktionskontext hinzufügen können SqlDataSource , wenn Sie das-Steuerelement zum Aktualisieren von Daten verwenden.The example shows how you can use a DbTransaction object to add transaction context when using the SqlDataSource control to update data.

<%@Page  Language="C#" %>
<%@Import Namespace="System.Data" %>
<%@Import Namespace="System.Data.Common" %>
<%@Import Namespace="System.Data.SqlClient" %>
<%@Import Namespace="System.Diagnostics" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

 private void On_Click(Object source, EventArgs e) {    
    SqlDataSource1.Update();
 }

 private void OnSqlUpdating(Object source, SqlDataSourceCommandEventArgs e) {
    DbCommand command = e.Command;
    DbConnection cx  = command.Connection;    
    cx.Open();    
    DbTransaction tx = cx.BeginTransaction();
    command.Transaction = tx;
 }

 private void OnSqlUpdated(Object source, SqlDataSourceStatusEventArgs e) {
    DbCommand command = e.Command;
    DbTransaction tx = command.Transaction;
    
    // In this code example the OtherProcessSucceeded variable represents
    // the outcome of some other process that occurs whenever the data is 
    // updated, and must succeed for the data change to be committed. For 
    // simplicity, we set this value to true. 
    bool OtherProcessSucceeded = true;
    
    if (OtherProcessSucceeded) {
        tx.Commit();
        Label2.Text="The record was updated successfully!";
    }
    else {
        tx.Rollback();
        Label2.Text="The record was not updated.";
    }
 }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">
      <asp:SqlDataSource
          id="SqlDataSource1"
          runat="server"
          ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
          SelectCommand="SELECT EmployeeID, LastName, Address FROM Employees"
          UpdateCommand="UPDATE Employees SET Address=@Address WHERE EmployeeID=@EmployeeID"
          OnUpdating="OnSqlUpdating"
          OnUpdated ="OnSqlUpdated">
          <UpdateParameters>
              <asp:ControlParameter Name="Address" ControlId="TextBox1" PropertyName="Text"/>
              <asp:ControlParameter Name="EmployeeID" ControlId="DropDownList1" PropertyName="SelectedValue"/>
          </UpdateParameters>
      </asp:SqlDataSource>

      <asp:DropDownList
          id="DropDownList1"
          runat="server"
          DataTextField="LastName"
          DataValueField="EmployeeID"
          DataSourceID="SqlDataSource1">
      </asp:DropDownList>

      <br />
      <asp:Label id="Label1" runat="server" Text="Enter a new address for the selected user."
        AssociatedControlID="TextBox1" />
      <asp:TextBox id="TextBox1" runat="server" />
      <asp:Button id="Submit" runat="server" Text="Submit" OnClick="On_Click" />

      <br /><asp:Label id="Label2" runat="server" Text="" />

    </form>
  </body>
</html>
<%@Page  Language="VB" %>
<%@Import Namespace="System.Data" %>
<%@Import Namespace="System.Data.Common" %>
<%@Import Namespace="System.Diagnostics" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

 Sub On_Click(ByVal source As Object, ByVal e As EventArgs)
        SqlDataSource1.Update()
 End Sub 'On_Click

 Sub On_Sql_Updating(ByVal source As Object, ByVal e As SqlDataSourceCommandEventArgs)
     Dim command as DbCommand
     Dim connection as DbConnection
     Dim transaction as DbTransaction
     
     command    = e.Command
     connection = command.Connection     
     connection.Open()     
     transaction = connection.BeginTransaction()
     command.Transaction = transaction
 
 End Sub 'On_Sql_Updating
 
 Sub On_Sql_Updated(ByVal source As Object, ByVal e As SqlDataSourceStatusEventArgs)
 
    Dim command As DbCommand
    Dim transaction As DbTransaction
    
    command = e.Command
    transaction = command.Transaction
    
    ' In this code example the OtherProcessSucceeded variable represents
    ' the outcome of some other process that occurs whenever the data is 
    ' updated, and must succeed for the data change to be committed. For 
    ' simplicity, we set this value to true. 
    Dim OtherProcessSucceeded as Boolean = True
    
    If (OtherProcessSucceeded) Then
        transaction.Commit()
        Label2.Text="The record was updated successfully!"
    Else    
        transaction.Rollback()
        Label2.Text="The record was not updated."
    End If
 End Sub ' On_Sql_Updated
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">
      <asp:SqlDataSource
          id="SqlDataSource1"
          runat="server"
          ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
          SelectCommand="SELECT EmployeeID, LastName, Address FROM Employees"
          UpdateCommand="UPDATE Employees SET Address=@Address WHERE EmployeeID=@EmployeeID"
          OnUpdating="On_Sql_Updating"
          OnUpdated ="On_Sql_Updated">
          <UpdateParameters>
              <asp:ControlParameter Name="Address" ControlId="TextBox1" PropertyName="Text"/>
              <asp:ControlParameter Name="EmployeeID" ControlId="DropDownList1" PropertyName="SelectedValue"/>
          </UpdateParameters>
      </asp:SqlDataSource>

      <asp:DropDownList
          id="DropDownList1"
          runat="server"
          DataTextField="LastName"
          DataValueField="EmployeeID"
          DataSourceID="SqlDataSource1">
      </asp:DropDownList>

      <br />
      <asp:Label id="Label1" runat="server" Text="Enter a new address for the selected user."
        AssociatedControlID="TextBox1" />
      <asp:TextBox id="TextBox1" runat="server" />
      <asp:Button id="Submit" runat="server" Text="Submit" OnClick="On_Click" />

      <br /><asp:Label id="Label2" runat="server" Text="" />

    </form>
  </body>
</html>

Hinweise

Indem Sie einen Ereignishandlerdelegaten Updatinghinzu Insertingfügen, Deleting um die Ereignisse, oder zu behandeln, können Sie jede zusätzliche Vorverarbeitung ausführen oder den Datenbankbefehl vollständig abbrechen.By adding an event handler delegate to handle the Updating, Inserting, or Deleting events, you can perform any additional preprocessing required or cancel the database command entirely.

Da die SqlDataSourceCommandEventArgs -Klasse von der CancelEventArgs -Klasse abgeleitet ist, können Sie einen SqlDataSource ausstehenden Datenbankbefehl abbrechen Cancel , indem trueSie die-Eigenschaft auf festlegen.Because the SqlDataSourceCommandEventArgs class is derived from the CancelEventArgs class, you can cancel a pending SqlDataSource database command by setting the Cancel property to true. Sie CommandTextkönnen die Parameters -Auflistung und andere Befehls Eigenschaften vor dem Ausführen des Befehls überprüfen und bearbeiten, indem Sie DbCommand auf das-Objekt Command zugreifen, das von der-Eigenschaft verfügbar gemacht wird.You can examine and manipulate the CommandText, Parameters collection, and other command properties prior to running the command by accessing the DbCommand object exposed by the Command property.

Die SqlDataSourceCommandEventArgs -Klasse wird in den OnUpdatingMethoden OnInserting, und OnDeleting verwendet, um den Zugriff auf SqlDataSource einen Datenbankbefehl bereitzustellen, bevor er ausgeführt wird.The SqlDataSourceCommandEventArgs class is used in the OnUpdating, OnInserting, and OnDeleting methods to provide access to a SqlDataSource database command before it is run. Das SqlDataSource -Steuerelement macht viele Ereignisse verfügbar, die Sie behandeln können, um während eines Daten Vorgangs mit den zugrunde liegenden Datenobjekten zu arbeiten.The SqlDataSource control exposes many events that you can handle to work with the underlying data objects during the course of a data operation. In der folgenden Tabelle werden die-Ereignisse EventArgs und zugeordneten-und-Ereignishandlerklassen aufgelistet, um Sie besser zu den verschiedenen Ereignissen zu führen, die SqlDataSource dem Lebenszyklus eines Daten Vorgangs mithilfe des-Steuer Elements entsprechen.The following table lists the events and associated EventArgs and event handler classes, to better guide you to the various events that correspond to the lifecycle of a data operation using the SqlDataSource control.

eventEvent EventArgsEventArgs EventHandlerEventHandler
SelectingTritt ein, bevor die Daten abgerufen werden.Selecting occurs before the data is retrieved. SqlDataSourceSelectingEventArgs SqlDataSourceSelectingEventHandler
Inserting, Updating ,Deleting treten vor einem INSERT-, Update-oder DELETE-Vorgang auf.Inserting, Updating, Deleting occur before an insert, update, or delete operation is performed. SqlDataSourceCommandEventArgs SqlDataSourceCommandEventHandler
Selected, Inserted, Updated ,Deleted treten nach Abschluss der Datenabruf-, INSERT-, Update-oder DELETE-Vorgänge auf.Selected, Inserted, Updated, Deleted occur after the data retrieval, insert, update, or delete operations completes. SqlDataSourceStatusEventArgs SqlDataSourceStatusEventHandler

Konstruktoren

SqlDataSourceCommandEventArgs(DbCommand) SqlDataSourceCommandEventArgs(DbCommand) SqlDataSourceCommandEventArgs(DbCommand) SqlDataSourceCommandEventArgs(DbCommand)

Initialisiert eine neue Instanz der SqlDataSourceCommandEventArgs-Klasse unter Verwendung des angegebenen Datenbankbefehlsobjekts.Initializes a new instance of the SqlDataSourceCommandEventArgs class, using the specified database command object.

Eigenschaften

Cancel Cancel Cancel Cancel

Ruft einen Wert ab, der angibt, ob das Ereignis abgebrochen werden soll, oder legt diesen fest.Gets or sets a value indicating whether the event should be canceled.

(Inherited from CancelEventArgs)
Command Command Command Command

Ruft den ausstehenden Datenbankbefehl ab.Gets the pending database command.

Methoden

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Bestimmt, ob das angegebene Objekt mit dem aktuellen Objekt identisch ist.Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Fungiert als Standardhashfunktion.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Ruft den Type der aktuellen Instanz ab.Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Erstellt eine flache Kopie des aktuellen Object.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Gibt eine Zeichenfolge zurück, die das aktuelle Objekt darstellt.Returns a string that represents the current object.

(Inherited from Object)

Gilt für:

Siehe auch