ControlCollection.Item[Int32] Eigenschaft

  • Referenz

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Ruft im ControlCollection-Objekt an der angegebenen Indexposition einen Verweis auf das Serversteuerelement ab

public:
 virtual property System::Web::UI::Control ^ default[int] { System::Web::UI::Control ^ get(int index); };
public virtual System.Web.UI.Control this[int index] { get; }
member this.Item(int) : System.Web.UI.Control
Default Public Overridable ReadOnly Property Item(index As Integer) As Control

Parameter

index
Int32

Die Position des Serversteuerelements in ControlCollection

Eigenschaftswert

Control

Der Verweis auf das Steuerelement.

Ausnahmen

ArgumentOutOfRangeException

Der index-Parameter ist kleiner als 0 (null) oder größer oder gleich Count.

Beispiele

Im folgenden Codebeispiel wird die Item[] Eigenschaft verwendet, um den Indexspeicherort eines untergeordneten Steuerelements anzugeben, das in einem Remove Methodenaufruf entfernt wird. Dies wird von der myButton.Controls.Remove Syntax ausgeführt.


<!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)
   {
       Response.Write("<h2>Sample for ControlCollection Class</h2>");

       LiteralControl myLiteralControl 
           = new LiteralControl("ChildControl1");

       myButton.Controls.Add(myLiteralControl);
       myButton.Controls.AddAt(1,new LiteralControl("ChildControl2"));

       System.Array myControlCollectionArray 
           = Array.CreateInstance(typeof(object), 
               myButton.Controls.Count);
       myButton.Controls.CopyTo(myControlCollectionArray,0);

       IEnumerator myEnumerator1 = 
           myControlCollectionArray.GetEnumerator();

       while (myEnumerator1.MoveNext())
       {
           object myObject = myEnumerator1.Current;

           if(myObject.GetType().Equals(typeof(LiteralControl)))
           {
               LiteralControl childControl = 
                   (LiteralControl)myEnumerator1.Current;
               Response.Write("<p style=\"font-weight:bold\">");
               Response.Write("This is the  text of the child Control:" 
                   + Server.HtmlEncode(childControl.Text));
           }
       }

       myButton.Controls.Remove(myButton.Controls[0]);
       Response.Write("</p><p style=\"font-weight:bold\">");
       Response.Write("ChildControl1 is removed<br />");
       Response.Write("The count of ControlCollection = "
           + myButton.Controls.Count.ToString() + "</p>");
       myButton.Controls.Clear();
   }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

        <asp:Button ID="myButton" Text="Sample ServerControl" 
            Runat="server"></asp:Button>

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


<!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)

        Response.Write("<h2>Sample for ControlCollection Class</h2>")
        Dim myLiteralControl As LiteralControl _
            = New LiteralControl("ChildControl1")

        myButton.Controls.Add(myLiteralControl)
        myButton.Controls.AddAt(1, New LiteralControl("ChildControl2"))

        Dim myControlCollectionArray As System.Array = _
            Array.CreateInstance(GetType(Object), _
                myButton.Controls.Count)
        myButton.Controls.CopyTo(myControlCollectionArray, 0)

        Dim myEnumerator1 As IEnumerator = _
            myControlCollectionArray.GetEnumerator()

        While myEnumerator1.MoveNext()
            Dim myObject As Object = myEnumerator1.Current

            If myObject.GetType().Equals(GetType(LiteralControl)) Then
                Dim childControl As LiteralControl _
                    = CType(myEnumerator1.Current, LiteralControl)
                Response.Write("<p style=""font-weight:bold"">")
                Response.Write("This is the  text of the child Control:" _
                    & Server.HtmlEncode(childControl.Text))
            End If
        End While

        myButton.Controls.Remove(myButton.Controls(0))
        Response.Write("</p><p style=""font-weight:bold"">ChildControl1 is removed")
        Response.Write("<br />The count of ControlCollection = " _
            & myButton.Controls.Count.ToString() & "</p>")
        myButton.Controls.Clear()

    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Sample for ControlCollection Class</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

        <asp:Button ID="myButton" Text="Sample ServerControl" 
            Runat="server"></asp:Button>
    
    </div>
    </form>
</body>
</html>

Gilt für

Siehe auch