通过

ToolBarButton.DropDownMenu 属性

  • 项目

获取或设置要显示在下拉工具栏按钮中的菜单。

**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）

语法

声明
Public Property DropDownMenu As Menu
用法
Dim instance As ToolBarButton
Dim value As Menu

value = instance.DropDownMenu

instance.DropDownMenu = value

public Menu DropDownMenu { get; set; }

public:
property Menu^ DropDownMenu {
    Menu^ get ();
    void set (Menu^ value);
}

/** @property */
public Menu get_DropDownMenu ()

/** @property */
public void set_DropDownMenu (Menu value)

public function get DropDownMenu () : Menu

public function set DropDownMenu (value : Menu)

属性值

要显示在下拉工具栏按钮中的 ContextMenu。默认为 空引用（在 Visual Basic 中为 Nothing）。

异常

异常类型 条件

ArgumentException

分配的对象不是 ContextMenu。

备注

可以指定在单击下拉按钮时要显示的 ContextMenu。不使用该属性，除非将 Style 属性值设置为 ToolBarButtonStyle.DropDownButton。

提示

尽管将 DropDownMenu 属性定义为 Menu 类型，仍必须给它分配一个 ContextMenu 以便它正确显示。如果您正创建自己的 MenuItem 派生类，则必须将该对象分配给 ContextMenu，并将 ContextMenu 分配给 DropDownMenu 属性。

示例

下面的代码示例创建一个 ToolBar 和三个 ToolBarButton 控件，将这些按钮分配给该工具栏，并设置按钮的一些通用属性。此代码要求已经创建 ImageList、ToolTip 和 Form，并且已经至少为此 ImageList 分配了一个 Image。

Public Sub InitializeMyToolBar()
    ' Create the ToolBar, ToolBarButton controls, and menus.
    Dim toolBarButton1 As New ToolBarButton("Open")
    Dim toolBarButton2 As New ToolBarButton()
    Dim toolBarButton3 As New ToolBarButton()
    Dim toolBar1 As New ToolBar()
Dim menuItem1 As New MenuItem("Print")
Dim contextMenu1 As New ContextMenu(New MenuItem(){menuItem1})
    
    ' Add the ToolBarButton controls to the ToolBar.
    toolBar1.Buttons.Add(toolBarButton1)
    toolBar1.Buttons.Add(toolBarButton2)
    toolBar1.Buttons.Add(toolBarButton3)
    
    ' Assign an ImageList to the ToolBar and show ToolTips.
    toolBar1.ImageList = imageList1
    toolBar1.ShowToolTips = True
    
    ' Assign ImageIndex, ContextMenu, Text, ToolTip, and
    ' Style properties of the ToolBarButton controls. 
    toolBarButton2.Style = ToolBarButtonStyle.Separator
    toolBarButton3.Text = "Print"
    toolBarButton3.Style = ToolBarButtonStyle.DropDownButton
    toolBarButton3.ToolTipText = "Print"
    toolBarButton3.ImageIndex = 0
    toolBarButton3.DropDownMenu = contextMenu1
    
    ' Add the ToolBar to a form.
    Controls.Add(toolBar1)
End Sub

public void InitializeMyToolBar()
 {
    // Create the ToolBar, ToolBarButton controls, and menus.
    ToolBarButton toolBarButton1 = new ToolBarButton("Open");
    ToolBarButton toolBarButton2 = new ToolBarButton();
    ToolBarButton toolBarButton3 = new ToolBarButton();
    ToolBar toolBar1 = new ToolBar();
    MenuItem menuItem1 = new MenuItem("Print");
    ContextMenu contextMenu1 = new ContextMenu(new MenuItem[]{menuItem1});

     
    // Add the ToolBarButton controls to the ToolBar.
    toolBar1.Buttons.Add(toolBarButton1);
    toolBar1.Buttons.Add(toolBarButton2);
    toolBar1.Buttons.Add(toolBarButton3);
 
    // Assign an ImageList to the ToolBar and show ToolTips.
    toolBar1.ImageList = imageList1;
    toolBar1.ShowToolTips = true;
 
    /* Assign ImageIndex, ContextMenu, Text, ToolTip, and 
       Style properties of the ToolBarButton controls. */
    toolBarButton2.Style = ToolBarButtonStyle.Separator;
    toolBarButton3.Text = "Print";
    toolBarButton3.Style = ToolBarButtonStyle.DropDownButton;
    toolBarButton3.ToolTipText = "Print";
    toolBarButton3.ImageIndex = 0;
    toolBarButton3.DropDownMenu = contextMenu1;
 
    // Add the ToolBar to a form.
    Controls.Add(toolBar1);
 }
 

public:
   void InitializeMyToolBar()
   {
      // Create the ToolBar, ToolBarButton controls, and menus.
      ToolBarButton^ toolBarButton1 = gcnew ToolBarButton( "Open" );
      ToolBarButton^ toolBarButton2 = gcnew ToolBarButton;
      ToolBarButton^ toolBarButton3 = gcnew ToolBarButton;
      ToolBar^ toolBar1 = gcnew ToolBar;
      MenuItem^ menuItem1 = gcnew MenuItem( "Print" );
      array<MenuItem^>^ temp1 = {menuItem1};
      System::Windows::Forms::ContextMenu^ contextMenu1 =
         gcnew System::Windows::Forms::ContextMenu( temp1 );
      
      // Add the ToolBarButton controls to the ToolBar.
      toolBar1->Buttons->Add( toolBarButton1 );
      toolBar1->Buttons->Add( toolBarButton2 );
      toolBar1->Buttons->Add( toolBarButton3 );
      
      // Assign an ImageList to the ToolBar and show ToolTips.
      toolBar1->ImageList = imageList1;
      toolBar1->ShowToolTips = true;
      
      /* Assign ImageIndex, ContextMenu, Text, ToolTip, and 
         Style properties of the ToolBarButton controls. */
      toolBarButton2->Style = ToolBarButtonStyle::Separator;
      toolBarButton3->Text = "Print";
      toolBarButton3->Style = ToolBarButtonStyle::DropDownButton;
      toolBarButton3->ToolTipText = "Print";
      toolBarButton3->ImageIndex = 0;
      toolBarButton3->DropDownMenu = contextMenu1;
      
      // Add the ToolBar to a form.
      Controls->Add( toolBar1 );
   }

public void InitializeMyToolBar()
{
    // Create the ToolBar, ToolBarButton controls, and menus.
    ToolBarButton toolBarButton1 = new ToolBarButton("Open");
    ToolBarButton toolBarButton2 = new ToolBarButton();
    ToolBarButton toolBarButton3 = new ToolBarButton();
    ToolBar toolBar1 = new ToolBar();
    MenuItem menuItem1 = new MenuItem("Print");
    ContextMenu contextMenu1 = new ContextMenu(new MenuItem[] {menuItem1});

    // Add the ToolBarButton controls to the ToolBar.
    toolBar1.get_Buttons().Add(toolBarButton1);
    toolBar1.get_Buttons().Add(toolBarButton2);
    toolBar1.get_Buttons().Add(toolBarButton3);

    // Assign an ImageList to the ToolBar and show ToolTips.
    toolBar1.set_ImageList(imageList1);
    toolBar1.set_ShowToolTips(true);

    /* Assign ImageIndex, ContextMenu, Text, ToolTip, and 
     * Style properties of the ToolBarButton controls. 
     */
    toolBarButton2.set_Style(ToolBarButtonStyle.Separator);
    toolBarButton3.set_Text("Print");
    toolBarButton3.set_Style(ToolBarButtonStyle.DropDownButton);
    toolBarButton3.set_ToolTipText("Print");
    toolBarButton3.set_ImageIndex(0);
    toolBarButton3.set_DropDownMenu(contextMenu1);

    // Add the ToolBar to a form.
    get_Controls().Add(toolBar1);
} //InitializeMyToolBar

平台

Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

.NET Compact Framework

受以下版本支持：2.0、1.0

请参见

参考

ToolBarButton 类
ToolBarButton 成员
System.Windows.Forms 命名空间
MenuItem 类