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MenuItem.ChildItems Property

Definition

Gets a MenuItemCollection object that contains the submenu items of the current menu item.

public:
 property System::Web::UI::WebControls::MenuItemCollection ^ ChildItems { System::Web::UI::WebControls::MenuItemCollection ^ get(); };
[System.ComponentModel.Browsable(false)]
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerDefaultProperty)]
public System.Web.UI.WebControls.MenuItemCollection ChildItems { get; }
[<System.ComponentModel.Browsable(false)>]
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerDefaultProperty)>]
member this.ChildItems : System.Web.UI.WebControls.MenuItemCollection
Public ReadOnly Property ChildItems As MenuItemCollection

Property Value

A MenuItemCollection that contains the submenu items of the current menu item. The default is null, which indicates that this menu item does not contain any submenu items.

Attributes

Examples

The following example demonstrates how to use the ChildItems property to traverse the menu items in a Menu control.


<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void Page_Load(Object sender, EventArgs e)
  {
    // If the Menu control contains any root nodes, perform a
    // preorder traversal of the tree and display the text of 
    // each node.
    if (NavigationMenu.Items.Count > 0)
    {

      // Iterate through the root menu items in the Items collection.
      foreach (MenuItem item in NavigationMenu.Items)
      {

        // Display the menu items.
        DisplayChildMenuText(item);

      }

    }
    else
    {

      Message.Text = "The Menu control does not have any items.";

    }
  }

  void DisplayChildMenuText(MenuItem item)
  {

    // Display the menu item's text value.
    Message.Text += item.Text + "<br />";

    // Iterate through the child menu items of the parent menu item 
    // passed into this method, and display their values.
    foreach (MenuItem childItem in item.ChildItems)
    {

      // Recursively call the DisplayChildMenuText method to
      // traverse the tree and display all child menu items.
      DisplayChildMenuText(childItem);

    }

  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>Menu Items Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>Menu Items Example</h3>
    
      <asp:menu id="NavigationMenu"
        staticdisplaylevels="2"
        staticsubmenuindent="10" 
        orientation="Vertical"
        runat="server">
      
        <items>
          <asp:menuitem text="Home"
            tooltip="Home">
            <asp:menuitem text="Music"
              tooltip="Music">
              <asp:menuitem text="Classical"
                tooltip="Classical"/>
              <asp:menuitem text="Rock"
                tooltip="Rock"/>
              <asp:menuitem text="Jazz"
                tooltip="Jazz"/>
            </asp:menuitem>
            <asp:menuitem text="Movies"
              tooltip="Movies">
              <asp:menuitem text="Action"
                tooltip="Action"/>
              <asp:menuitem text="Drama"
                tooltip="Drama"/>
              <asp:menuitem text="Musical"
                tooltip="Musical"/>
            </asp:menuitem>
          </asp:menuitem>
        </items>
      
      </asp:menu>
      
      <hr/>
      
      <asp:label id="Message" 
        runat="server"/>

    </form>
  </body>
</html>

<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    ' If the Menu control contains any root nodes, perform a
    ' preorder traversal of the tree and display the text of 
    ' each node.
    If NavigationMenu.Items.Count > 0 Then
    

      ' Iterate through the root menu items in the Items collection.
      Dim item As MenuItem
      For Each item In NavigationMenu.Items

        ' Display the menu items.
        DisplayChildMenuText(item)

      Next

    Else

      Message.Text = "The Menu control does not have any items."

    End If
      
  End Sub

  Sub DisplayChildMenuText(ByVal item As MenuItem)

    ' Display the menu item's text value.
    Message.Text &= item.Text & "<br />"

    ' Iterate through the child menu items of the parent menu item 
    ' passed into this method, and display their values.
    Dim childItem As MenuItem
    For Each childItem In item.ChildItems

      ' Recursively call the DisplayChildMenuText method to
      ' traverse the tree and display all child menu items.
      DisplayChildMenuText(childItem)

    Next

  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>Menu Items Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>Menu Items Example</h3>
    
      <asp:menu id="NavigationMenu"
        staticdisplaylevels="2"
        staticsubmenuindent="10" 
        orientation="Vertical"
        runat="server">
      
        <items>
          <asp:menuitem text="Home"
            tooltip="Home">
            <asp:menuitem text="Music"
              tooltip="Music">
              <asp:menuitem text="Classical"
                tooltip="Classical"/>
              <asp:menuitem text="Rock"
                tooltip="Rock"/>
              <asp:menuitem text="Jazz"
                tooltip="Jazz"/>
            </asp:menuitem>
            <asp:menuitem text="Movies"
              tooltip="Movies">
              <asp:menuitem text="Action"
                tooltip="Action"/>
              <asp:menuitem text="Drama"
                tooltip="Drama"/>
              <asp:menuitem text="Musical"
                tooltip="Musical"/>
            </asp:menuitem>
          </asp:menuitem>
        </items>
      
      </asp:menu>
      
      <hr/>
      
      <asp:label id="Message" 
        runat="server"/>

    </form>
  </body>
</html>

Remarks

Use the ChildItems property (collection) to access the submenu items of the current menu item, if any. This collection contains only the menu items at the next level. To access menu items further down the menu tree, use the ChildItems property of a subsequent menu item. If the ChildItems property is null, the current menu does not have any submenu items.

The ChildItems property can also be used to programmatically manage the submenu items of the current menu item. You can add, insert, remove, retrieve, and modify MenuItem objects from the collection. Any updates to the collection will automatically be reflected in the Menu control the next time the page is refreshed.

Applies to

See also