Add Method

ControlCollection.Add Method

Adds the specified Control object to the collection.

Namespace: System.Web.UI
Assembly: System.Web (in system.web.dll)

Public Overridable Sub Add ( _
	child As Control _
Dim instance As ControlCollection
Dim child As Control

public void Add (
	Control child
public function Add (
	child : Control
Not applicable.



The Control to add to the collection.

Exception typeCondition


Thrown if the child parameter does not specify a control.


Thrown if the ControlCollection is read-only.

The new control is added to the end of an ordinal index array. The control can be an instance of any ASP.NET server control, a custom server control you create, or a literal control.

To add a control to the collection at a specific index location, use the AddAt method.

The following code example uses the Add method to add a series of template items, the number of which are taken from the server control's view state, to a custom templated control.

' Override to create repeated items.
Protected Overrides Sub CreateChildControls()
    Dim O As Object = ViewState("NumItems")
    If Not (O Is Nothing)
       ' Clear any existing child controls.

       Dim I As Integer
       Dim NumItems As Integer = CInt(O)
       For I = 0 To NumItems - 1
          ' Create an item.
          Dim Item As RepeaterItemVB = New RepeaterItemVB(I, Nothing)
          ' Initialize the item from the template.
          ' Add the item to the ControlCollection.
    End If
End Sub

// Override to create repeated items.
protected void CreateChildControls()
    Object o = get_ViewState().get_Item("NumItems");
    if (o != null) {
        // Clear any existing child controls.

        int numItems = Convert.ToInt32(o);
        for (int i = 0; i < numItems; i++) {
            // Create an item.
            RepeaterItem item = new RepeaterItem(i, null);
            // Initialize the item from the template.
            // Add the item to the ControlCollection.
} //CreateChildControls

Windows 98, Windows Server 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

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