ControlCollection.Clear Method
Definition
Important
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Removes all controls from the current server control's ControlCollection object.
public:
virtual void Clear();
public virtual void Clear ();
abstract member Clear : unit -> unit
override this.Clear : unit -> unit
Public Overridable Sub Clear ()
Examples
The following code example demonstrates overriding the Control.CreateChildControls method, and using the Clear method to delete all child controls previously in the ControlCollection object. In this case, you must do this so that outdated objects in your control's ControlCollection are not displayed inappropriately.
// Override to create repeated items.
protected override void CreateChildControls() {
object o = ViewState["NumItems"];
if (o != null) {
// Clear any existing child controls.
Controls.Clear();
int numItems = (int)o;
for (int i=0; i < numItems; i++) {
// Create an item.
RepeaterItem item = new RepeaterItem(i, null);
// Initialize the item from the template.
ItemTemplate.InstantiateIn(item);
// Add the item to the ControlCollection.
Controls.Add(item);
}
}
}
' 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.
Controls.Clear()
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.
ItemTemplate.InstantiateIn(Item)
' Add the item to the ControlCollection.
Controls.Add(Item)
Next
End If
End Sub
Remarks
Use this method to empty a custom control's ControlCollection when you override the Control.CreateChildControls and DataBind methods. Do this when you develop composite, templated controls or templated data-bound controls.