MenuItem.OnClick(EventArgs) 方法

定义

引发 Click 事件。Raises the Click event.

protected:
 virtual void OnClick(EventArgs ^ e);
protected virtual void OnClick (EventArgs e);
abstract member OnClick : EventArgs -> unit
override this.OnClick : EventArgs -> unit
Protected Overridable Sub OnClick (e As EventArgs)

参数

e
EventArgs

包含事件数据的 EventArgsAn EventArgs that contains the event data.

示例

下面的代码示例演示如何使用 Click 事件在单击 MenuItem 时执行任务。The following code example demonstrates how to use the Click event to perform tasks when a MenuItem is clicked. 该示例创建一个名为 mainMenu1MainMenu,并添加两个 MenuItem 对象: topMenuItemFile)和 menuItem1Open)。The example creates a MainMenu called mainMenu1 and adds two MenuItem objects, topMenuItem (File) and menuItem1 (Open). 然后,它将 Click 事件连接到 menuItem1_Click 事件处理程序。It then connects the Click event to the menuItem1_Click event handler. 当用户单击 "Open" 菜单项时,将初始化并显示 OpenFileDialogWhen the user clicks the Open menu item, an OpenFileDialog is initialized and displayed. 该示例要求您已创建一个名为 Form1FormThe example requires that you have created a Form named Form1.

public:
   void CreateMyMenu()
   {
      // Create a main menu object.
      MainMenu^ mainMenu1 = gcnew MainMenu;

      // Create empty menu item objects.
      MenuItem^ topMenuItem = gcnew MenuItem;
      MenuItem^ menuItem1 = gcnew MenuItem;

      // Set the caption of the menu items.
      topMenuItem->Text = "&File";
      menuItem1->Text = "&Open";

      // Add the menu items to the main menu.
      topMenuItem->MenuItems->Add( menuItem1 );
      mainMenu1->MenuItems->Add( topMenuItem );

      // Add functionality to the menu items using the Click event. 
      menuItem1->Click += gcnew System::EventHandler( this, &Form1::menuItem1_Click );

      // Assign mainMenu1 to the form.
      this->Menu = mainMenu1;
   }

private:
   void menuItem1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Create a new OpenFileDialog and display it.
      OpenFileDialog^ fd = gcnew OpenFileDialog;
      fd->DefaultExt = "*.";
      fd->ShowDialog();
   }
public void CreateMyMenu()
{
    // Create a main menu object.
    MainMenu mainMenu1 = new MainMenu();

    // Create empty menu item objects.
    MenuItem topMenuItem = new MenuItem();
    MenuItem menuItem1 = new MenuItem();
          
    // Set the caption of the menu items.
    topMenuItem.Text = "&File";
    menuItem1.Text = "&Open";

    // Add the menu items to the main menu.
        topMenuItem.MenuItems.Add(menuItem1);
    mainMenu1.MenuItems.Add(topMenuItem);
                
    // Add functionality to the menu items using the Click event. 
    menuItem1.Click += new System.EventHandler(this.menuItem1_Click);

    // Assign mainMenu1 to the form.
    this.Menu=mainMenu1;
}

private void menuItem1_Click(object sender, System.EventArgs e)
{	
           // Create a new OpenFileDialog and display it.
   OpenFileDialog fd = new OpenFileDialog();
       fd.DefaultExt = "*.*";
   fd.ShowDialog();
}
 Public Sub CreateMyMenu()
   ' Create a main menu object.
   Dim mainMenu1 As New MainMenu()

   ' Create empty menu item objects.
   Dim topMenuItem As New MenuItem()
   Dim menuItem1 As New MenuItem()

   ' Set the caption of the menu items.
   topMenuItem.Text = "&File"
   menuItem1.Text = "&Open"

   ' Add the menu items to the main menu.
   topMenuItem.MenuItems.Add(menuItem1)
   mainMenu1.MenuItems.Add(topMenuItem)

   ' Add functionality to the menu items using the Click event. 
   AddHandler menuItem1.Click, AddressOf Me.menuItem1_Click
   ' Assign mainMenu1 to the form.
   Me.Menu = mainMenu1
End Sub


Private Sub menuItem1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
   ' Create a new OpenFileDialog and display it.
   Dim fd As New OpenFileDialog()
   fd.DefaultExt = "*.*"
   fd.ShowDialog()
End Sub

注解

引发事件时,将通过委托调用事件处理程序。Raising an event invokes the event handler through a delegate. 有关详细信息,请参阅处理和引发事件For more information, see Handling and Raising Events.

继承者说明

当在派生类中重写 OnClick(EventArgs) 时,请确保调用基类的 OnClick(EventArgs) 方法。When overriding OnClick(EventArgs) in a derived class, be sure to call the base class's OnClick(EventArgs) method.

适用于