MenuItemCollection.IndexOf(MenuItem) Methode
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Bestimmt den Index des angegebenen MenuItem-Objekts in der Auflistung.
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 -> intPublic Function IndexOf (value As MenuItem) As IntegerParameter
Gibt zurück
Der nullbasierte Index des ersten Vorkommens von value in der aktuellen MenuItemCollection (sofern gefunden), andernfalls -1.
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie die Methode verwendet IndexOf wird, um den Index eines Objekts innerhalb eines MenuItem MenuItemCollection Objekts zu bestimmen.
<%@ 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>
Hinweise
Verwenden Sie die IndexOf Methode, um den Index des angegebenen MenuItem Objekts im aktuellen MenuItemCollection Objekt zu bestimmen. Wenn sich das Menüelement nicht in der Auflistung befindet, gibt die Methode -1 zurück.
Hinweis
Wenn das angegebene Menüelement mehrmals in der Auflistung angezeigt wird, wird der Index des ersten Vorkommens zurückgegeben.