ComponentChangedEventHandler 委托

定义

表示用来处理 ComponentChanged 事件的方法。Represents the method that will handle a ComponentChanged event.

public delegate void ComponentChangedEventHandler(System::Object ^ sender, ComponentChangedEventArgs ^ e);
[System.Runtime.InteropServices.ComVisible(true)]
public delegate void ComponentChangedEventHandler(object sender, ComponentChangedEventArgs e);
type ComponentChangedEventHandler = delegate of obj * ComponentChangedEventArgs -> unit
Public Delegate Sub ComponentChangedEventHandler(sender As Object, e As ComponentChangedEventArgs)

参数

sender
Object

事件源。The source of the event.

e
ComponentChangedEventArgs

包含事件数据的 ComponentChangedEventArgsA ComponentChangedEventArgs that contains the event data.

继承
ComponentChangedEventHandler
属性

示例

此示例演示如何注册ComponentChangedEventHandlerComponentChanged处理事件。This example demonstrates registering a ComponentChangedEventHandler and handling the ComponentChanged event.

public:
   void LinkComponentChangedEvent( IComponentChangeService^ changeService )
   {
      // Registers an event handler for the ComponentChanged event.
      changeService->ComponentChanged += gcnew ComponentChangedEventHandler(
         this, &ComponentChangedEventHandlerExample::OnComponentChanged );
   }

private:
   void OnComponentChanged( Object^ sender, ComponentChangedEventArgs^ e )
   {
      // Displays changed component information on the console.
      Console::WriteLine( "Type of the component that has changed: " +
         e->Component->GetType()->FullName );
      Console::WriteLine( "Name of the member of the component that has changed: " +
         e->Member->Name );
      Console::WriteLine( "Old value of the member: " + e->OldValue );
      Console::WriteLine( "New value of the member: " + e->NewValue );
   }
public void LinkComponentChangedEvent(IComponentChangeService changeService)
{
    // Registers an event handler for the ComponentChanged event.
    changeService.ComponentChanged += new ComponentChangedEventHandler(this.OnComponentChanged);            
}

private void OnComponentChanged(object sender, ComponentChangedEventArgs e)
{
    // Displays changed component information on the console.
    Console.WriteLine("Type of the component that has changed: "+e.Component.GetType().FullName);      
    Console.WriteLine("Name of the member of the component that has changed: "+e.Member.Name);            
    Console.WriteLine("Old value of the member: "+e.OldValue.ToString());
    Console.WriteLine("New value of the member: "+e.NewValue.ToString());
}
Public Sub LinkComponentChangedEvent(ByVal changeService As IComponentChangeService)
    ' Registers an event handler for the ComponentChanged event.
    AddHandler changeService.ComponentChanged, AddressOf Me.OnComponentChanged
End Sub

Private Sub OnComponentChanged(ByVal sender As Object, ByVal e As ComponentChangedEventArgs)
    ' Displays changed component information on the console.            
    Console.WriteLine(("Type of the component that has changed: " + e.Component.GetType().FullName))
    Console.WriteLine(("Name of the member of the component that has changed: " + e.Member.Name))
    Console.WriteLine(("Old value of the member: " + e.OldValue.ToString()))
    Console.WriteLine(("New value of the member: " + e.NewValue.ToString()))
End Sub

注解

创建 ComponentChangedEventHandler 委托时,需要标识将处理该事件的方法。When you create a ComponentChangedEventHandler delegate, you identify the method that will handle the event. 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。To associate the event with your event handler, add an instance of the delegate to the event. 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。The event handler is called whenever the event occurs, unless you remove the delegate. 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For more information about event-handler delegates, see Handling and Raising Events.

在加载或卸载窗体的过程中不会发生事件,因为在这些操作期间需要进行更改。ComponentChangedA ComponentChanged event will not occur during the loading or unloading of a form because changes are expected during these operations.

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。Gets an object that represents the method represented by the specified delegate.

适用于

另请参阅