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Control.HasControls Method

Determines if the server control contains any child controls.

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

public virtual bool HasControls()

Return Value

Type: System.Boolean
true if the control contains other controls; otherwise, false.

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 Extending Metadata Using Attributes.

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);
                 }
   }

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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