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Control.HasControls Method

Definition

Determines if the server control contains any child controls.

public:
 virtual bool HasControls();
public virtual bool HasControls ();
abstract member HasControls : unit -> bool
override this.HasControls : unit -> bool
Public Overridable Function HasControls () As Boolean

Returns

true if the control contains other controls; otherwise, false.

Examples

The following example uses the HasControls method to determine if any controls exist before using the Count property to iterate through a ControlCollection object.

if (HasControls()) {
                 for (int i=0; i < Controls.Count; i++) {
                     Controls[i].RenderControl(writer);
                 }
   }
If HasControls() Then
    Dim i As Integer
    For i = 0 To Controls.Count - 1
        Controls(i).RenderControl(writer)
    Next i
End If

Remarks

Since this method simply determines if any child controls exist, it can enhance performance by allowing you to avoid an unnecessary Count property call. Calls to this property require a ControlCollection object to be instantiated. If there are no children, this object creation wastes server resources.

Notes to Inheritors

The HasControls() method should be overridden only to change metadata attributes such as EditorBrowsableAttribute. For more information about using attributes, see Attributes.

Applies to

See also