DesignerTransactionCloseEventHandler 委托

定义

命名空间:

System.ComponentModel.Design

程序集:

System.ComponentModel.TypeConverter.dll

表示处理设计器的 TransactionClosed 和 TransactionClosing 事件的方法。

public delegate void DesignerTransactionCloseEventHandler(System::Object ^ sender, DesignerTransactionCloseEventArgs ^ e);

public delegate void DesignerTransactionCloseEventHandler(object? sender, DesignerTransactionCloseEventArgs e);

type DesignerTransactionCloseEventHandler = delegate of obj * DesignerTransactionCloseEventArgs -> unit

Public Delegate Sub DesignerTransactionCloseEventHandler(sender As Object, e As DesignerTransactionCloseEventArgs)

参数

sender

Object

事件源。

e

DesignerTransactionCloseEventArgs

包含事件数据的 DesignerTransactionCloseEventArgs。

示例

以下示例演示如何注册 DesignerTransactionCloseEventHandler 并处理 TransactionClosing 和 TransactionClosed 事件。

public:
   void LinkDesignerTransactionCloseEvent( IDesignerHost^ host )
   {
      // Registers an event handler for the designer TransactionClosing and TransactionClosed events.
      host->TransactionClosing += gcnew DesignerTransactionCloseEventHandler(
         this, &DesignerTransactionCloseEventHandlerExample::OnTransactionClose );
      host->TransactionClosed += gcnew DesignerTransactionCloseEventHandler(
         this, &DesignerTransactionCloseEventHandlerExample::OnTransactionClose );
   }

private:
   void OnTransactionClose( Object^ sender, DesignerTransactionCloseEventArgs^ e )
   {
      // Displays transaction close information on the console.
      if ( e->TransactionCommitted )
      {
         Console::WriteLine( "Transaction has been committed." );
      }
      else
      {
         Console::WriteLine( "Transaction has not yet been committed." );
      }
   }

public void LinkDesignerTransactionCloseEvent(IDesignerHost host)
{                       
    // Registers an event handler for the designer TransactionClosing and TransactionClosed events.
    host.TransactionClosing += new DesignerTransactionCloseEventHandler(this.OnTransactionClose);
    host.TransactionClosed += new DesignerTransactionCloseEventHandler(this.OnTransactionClose);
}

private void OnTransactionClose(object sender, DesignerTransactionCloseEventArgs e)
{
    // Displays transaction close information on the console.           
    if( e.TransactionCommitted )            
        Console.WriteLine("Transaction has been committed.");
    else
        Console.WriteLine("Transaction has not yet been committed.");
}

Public Sub LinkDesignerTransactionCloseEvent(ByVal host As IDesignerHost)
    ' Registers an event handler for the designer TransactionClosing 
    ' and TransactionClosed events.
    AddHandler host.TransactionClosing, AddressOf Me.OnTransactionClose
    AddHandler host.TransactionClosed, AddressOf Me.OnTransactionClose
End Sub

Private Sub OnTransactionClose(ByVal sender As Object, ByVal e As DesignerTransactionCloseEventArgs)
    ' Displays transaction close information on the console.           
    If e.TransactionCommitted Then
        Console.WriteLine("Transaction has been committed.")
    Else
        Console.WriteLine("Transaction has not yet been committed.")
    End If
End Sub

注解

创建 DesignerTransactionCloseEventHandler 委托时，需要标识将处理该事件的方法。 若要将事件与事件处理程序关联，请将该委托的一个实例添加到事件中。 除非移除了该委托，否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息，请参阅 处理和引发事件。

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。

另请参阅

• IDesignerHost