MenuItemCollection.IndexOf(MenuItem) Method

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

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Determines the index of the specified MenuItem object in the collection.

public:
 int IndexOf(System::Web::UI::WebControls::MenuItem ^ value);

public int IndexOf (System.Web.UI.WebControls.MenuItem value);

member this.IndexOf : System.Web.UI.WebControls.MenuItem -> int

Public Function IndexOf (value As MenuItem) As Integer

Parameters

value: MenuItem

The MenuItem to locate.

Returns

Int32

The zero-based index of the first occurrence of value within the current MenuItemCollection, if found; otherwise, -1.

Examples

The following code example demonstrates how to use the IndexOf method to determine the index of a MenuItem object within a MenuItemCollection object.


<%@ 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 NavigationMenu_MenuItemClick(Object sender, MenuEventArgs e)
  {

    // Retrieve the parent menu item of the selected menu item.
    MenuItem parent = e.Item.Parent;

    // Determine whether the selected menu item is a 
    // root menu item. Root menu items are stored in
    // a Menu control's Items collection. Other menu
    // items are stored in the parent menu item's
    // ChildItems collection.
    if (parent != null)
    {
      Message.Text = "The " + e.Item.Text + 
        " menu item has an index of " +
        parent.ChildItems.IndexOf(e.Item).ToString() +
        " in the parent menu item's ChildItems collection.";
    }
    else
    {
      Message.Text = "The " + e.Item.Text +
        " menu item has an index of " +
        NavigationMenu.Items.IndexOf(e.Item).ToString() +
        " in the Menu control's Items collection.";
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>MenuItemCollection IndexOf Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>MenuItemCollection IndexOf Example</h3>
    
      Select an item from the menu.
      <br/><br/>
    
      <asp:menu id="NavigationMenu"
        orientation="Vertical"
        target="_blank"
        onmenuitemclick="NavigationMenu_MenuItemClick"  
        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 NavigationMenu_MenuItemClick(ByVal sender As Object, ByVal e As MenuEventArgs)

    ' Retrieve the parent menu item of the selected menu item.
    Dim parent As MenuItem = e.Item.Parent

    ' Determine whether the selected menu item is a 
    ' root menu item. Root menu items are stored in
    ' a Menu control's Items collection. Other menu
    ' items are stored in the parent menu item's
    ' ChildItems collection.
    If parent IsNot Nothing Then
    
      Message.Text = "The " & e.Item.Text & _
        " menu item has an index of " & _
        parent.ChildItems.IndexOf(e.Item).ToString() & _
        " in the parent menu item's ChildItems collection."
    
    Else
    
      Message.Text = "The " & e.Item.Text & _
        " menu item has an index of " & _
        NavigationMenu.Items.IndexOf(e.Item).ToString() & _
        " in the Menu control's Items collection."
    
    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>MenuItemCollection IndexOf Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>MenuItemCollection IndexOf Example</h3>
    
      Select an item from the menu.
      <br/><br/>
    
      <asp:menu id="NavigationMenu"
        orientation="Vertical"
        target="_blank"
        onmenuitemclick="NavigationMenu_MenuItemClick"  
        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 IndexOf method to determine the index of the specified MenuItem object in the current MenuItemCollection object. If the menu item is not in the collection, the method returns -1.

Note

If the specified menu item appears multiple times in the collection, the index of the first occurrence is returned.

Applies to

Dela via