GridViewDeletedEventHandler Delegat

Referenz

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Stellt die Methode dar, die das RowDeleted-Ereignis eines GridView-Steuerelements behandelt.

public delegate void GridViewDeletedEventHandler(System::Object ^ sender, GridViewDeletedEventArgs ^ e);

public delegate void GridViewDeletedEventHandler(object sender, GridViewDeletedEventArgs e);

type GridViewDeletedEventHandler = delegate of obj * GridViewDeletedEventArgs -> unit

Public Delegate Sub GridViewDeletedEventHandler(sender As Object, e As GridViewDeletedEventArgs)

Parameter

sender: Object

Die Quelle des Ereignisses.

e: GridViewDeletedEventArgs

Ein GridViewDeletedEventArgs, das die Ereignisdaten enthält.

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie dem Ereignis eines Steuerelements programmgesteuert ein GridViewDeletedEventHandler GridView Delegat RowDeleted hinzugefügt wird.


<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
  
  void Page_Load(Object sender, EventArgs e)
  {

    // Create a new GridView control.
    GridView customersGridView = new GridView();
    
    // Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView";
    customersGridView.DataSourceID = "CustomersSqlDataSource";
    customersGridView.AutoGenerateColumns = true;
    customersGridView.AutoGenerateDeleteButton = true;
    customersGridView.DataKeyNames = new String[1] { "CustomerID" };

    // Programmatically register the event-handling method
    // for the RowDeleted event of the GridView control.
    customersGridView.RowDeleted += new GridViewDeletedEventHandler(this.CustomersGridView_RowDeleted);

    // Add the GridView control to the Controls collection
    // of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView);
    
  }

  void CustomersGridView_RowDeleted(Object sender, GridViewDeletedEventArgs e)
  {
    
    // Display whether the delete operation succeeded.
    if(e.Exception == null)
    {
      Message.Text = "Row deleted successfully.";
    }
    else
    {
      Message.Text = "An error occurred while attempting to deleting the row.";
      e.ExceptionHandled = true;   
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeletedEventHandler Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
      
      <asp:placeholder id="GridViewPlaceHolder"
        runat="server"/>
            
      <!-- 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" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
  
  Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    ' Create a new GridView control.
    Dim customersGridView As New GridView()
    
    ' Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView"
    customersGridView.DataSourceID = "CustomersSqlDataSource"
    customersGridView.AutoGenerateColumns = True
    customersGridView.AutoGenerateDeleteButton = True
    
    Dim keyArray() As String = {"CustomerID"}
    customersGridView.DataKeyNames = keyArray

    ' Programmatically register the event-handling method
    ' for the RowDeleted event of the GridView control.
    AddHandler customersGridView.RowDeleted, AddressOf CustomersGridView_RowDeleted

    ' Add the GridView control to the Controls collection
    ' of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView)
    
  End Sub

  Sub CustomersGridView_RowDeleted(ByVal sender As Object, ByVal e As GridViewDeletedEventArgs)
    
    ' Display whether the delete operation succeeded.
    If e.Exception Is Nothing Then
    
      Message.Text = "Row deleted successfully."
    
    Else
          
      Message.Text = "An error occurred while attempting to deleting the row."
      e.ExceptionHandled = True
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeletedEventHandler Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
      
      <asp:placeholder id="GridViewPlaceHolder"
        runat="server"/>
            
      <!-- 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>

Im folgenden Beispiel wird veranschaulicht, wie dem Ereignis eines Steuerelements deklarativ ein GridViewDeletedEventHandler GridView Delegat RowDeleted hinzugefügt wird.


<%@ Page language="C#" %>

<!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_RowDeleted(Object sender, GridViewDeletedEventArgs e)
  {
    
    // Display whether the delete operation succeeded.
    if(e.Exception == null)
    {
      Message.Text = "Row deleted successfully.";
    }
    else
    {
      Message.Text = "An error occurred while attempting to delete the row.";
      e.ExceptionHandled = true;   
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowDeleted Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowDeleted Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
            
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true"
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"  
        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" %>

<!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_RowDeleted(sender As Object, e As GridViewDeletedEventArgs)
    
    ' Display whether the delete operation succeeded.
    If e.Exception Is Nothing Then
    
      Message.Text = "Row deleted successfully."
    
    Else
          
      Message.Text = "An error occurred while attempting to delete the row."
      e.ExceptionHandled = True
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowDeleted Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowDeleted Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true"
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"  
        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>

Hinweise

Das GridView -Steuerelement löst das RowDeleted -Ereignis aus, wenn auf eine Schaltfläche "Löschen" (eine Schaltfläche mit der auf "Löschen" gesetzten CommandName Eigenschaft) innerhalb des Steuerelements geklickt wird, aber nachdem das GridView Steuerelement den Datensatz gelöscht hat. Auf diese Weise können Sie eine Ereignisbehandlungsmethode bereitstellen, die eine benutzerdefinierte Routine ausführt, z. B. die Überprüfung der Ergebnisse eines Löschvorgangs, wenn dieses Ereignis auftritt.

Beim Erstellen eines GridViewDeletedEventHandler-Delegaten bestimmen Sie die Methode für die Ereignisbehandlung. Um dem Ereignishandler das Ereignis zuzuordnen, fügen Sie dem Ereignis eine Instanz des Delegaten hinzu. Der Ereignishandler wird bei jedem Eintreten des Ereignisses aufgerufen, sofern der Delegat nicht entfernt wird. Weitere Informationen zu Ereignishandlerdelegaten finden Sie unter Behandeln und Auslösen von Ereignissen.

Erweiterungsmethoden

GetMethodInfo(Delegate)

Ruft ein Objekt ab, das die Methode darstellt, die vom angegebenen Delegaten dargestellt wird.

Gilt für:

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