ToolStripDropDownItem.DropDown 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

获取或设置单击此 ToolStripDropDown 时将显示的 ToolStripDropDownItem。

public:
 property System::Windows::Forms::ToolStripDropDown ^ DropDown { System::Windows::Forms::ToolStripDropDown ^ get(); void set(System::Windows::Forms::ToolStripDropDown ^ value); };

[System.ComponentModel.TypeConverter(typeof(System.ComponentModel.ReferenceConverter))]
public System.Windows.Forms.ToolStripDropDown DropDown { get; set; }

[<System.ComponentModel.TypeConverter(typeof(System.ComponentModel.ReferenceConverter))>]
member this.DropDown : System.Windows.Forms.ToolStripDropDown with get, set

Public Property DropDown As ToolStripDropDown

属性值

ToolStripDropDown

与 ToolStripDropDown 关联的 ToolStripDropDownItem。

属性

TypeConverterAttribute

示例

下面的代码示例演示如何将 ContextMenuStrip 控件分配给 ToolStripDropDownItem 控件的 DropDown 属性。 此代码示例是为 ToolStripDropDownItem 类提供的一个更大示例的一部分。

// This utility method creates and initializes three 
// ToolStripDropDownItem controls and adds them 
// to the form's ToolStrip control.
private void InitializeToolStripDropDownItems()
{
    ToolStripDropDownButton b = new ToolStripDropDownButton("DropDownButton");
    b.DropDown = this.contextMenuStrip1;
    b.DropDownClosed += new EventHandler(toolStripDropDownItem_DropDownClosed);
    b.DropDownItemClicked += new ToolStripItemClickedEventHandler(toolStripDropDownItem_DropDownItemClicked);
    b.DropDownOpened += new EventHandler(toolStripDropDownItem_DropDownOpened);

    ToolStripMenuItem m = new ToolStripMenuItem("MenuItem");
    m.DropDown = this.contextMenuStrip1;
    m.DropDownClosed += new EventHandler(toolStripDropDownItem_DropDownClosed);
    m.DropDownItemClicked += new ToolStripItemClickedEventHandler(toolStripDropDownItem_DropDownItemClicked);
    m.DropDownOpened += new EventHandler(toolStripDropDownItem_DropDownOpened);

    ToolStripSplitButton sb = new ToolStripSplitButton("SplitButton");
    sb.DropDown = this.contextMenuStrip1;
    sb.DropDownClosed += new EventHandler(toolStripDropDownItem_DropDownClosed);
    sb.DropDownItemClicked += new ToolStripItemClickedEventHandler(toolStripDropDownItem_DropDownItemClicked);
    sb.DropDownOpened += new EventHandler(toolStripDropDownItem_DropDownOpened);

    this.toolStrip1.Items.AddRange(new ToolStripItem[] { b, m, sb });
}

' This utility method creates and initializes three 
' ToolStripDropDownItem controls and adds them 
' to the form's ToolStrip control.
Private Sub InitializeToolStripDropDownItems()
   Dim b As New ToolStripDropDownButton("DropDownButton")
   b.DropDown = Me.contextMenuStrip1
   AddHandler b.DropDownClosed, AddressOf toolStripDropDownItem_DropDownClosed
   AddHandler b.DropDownItemClicked, AddressOf toolStripDropDownItem_DropDownItemClicked
   AddHandler b.DropDownOpened, AddressOf toolStripDropDownItem_DropDownOpened
   
   Dim m As New ToolStripMenuItem("MenuItem")
   m.DropDown = Me.contextMenuStrip1
   AddHandler m.DropDownClosed, AddressOf toolStripDropDownItem_DropDownClosed
   AddHandler m.DropDownItemClicked, AddressOf toolStripDropDownItem_DropDownItemClicked
   AddHandler m.DropDownOpened, AddressOf toolStripDropDownItem_DropDownOpened
   
   Dim sb As New ToolStripSplitButton("SplitButton")
   sb.DropDown = Me.contextMenuStrip1
   AddHandler sb.DropDownClosed, AddressOf toolStripDropDownItem_DropDownClosed
   AddHandler sb.DropDownItemClicked, AddressOf toolStripDropDownItem_DropDownItemClicked
   AddHandler sb.DropDownOpened, AddressOf toolStripDropDownItem_DropDownOpened
   
   Me.toolStrip1.Items.AddRange(New ToolStripItem() {b, m, sb})
End Sub

注解

ToolStripDropDown如果未与 关联，ToolStripDropDownItem则调用 将CreateDefaultDropDown创建泛型下拉控件。

注意

如果自动生成下拉控件，这意味着项已添加到集合中，然后将 属性 DropDown 设置为显式下拉控件，则可能会丢失数据。