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ExpandCollapsePattern Class

Represents controls that visually expand to display content and collapse to hide content.


Namespace:  System.Windows.Automation
Assembly:  UIAutomationClient (in UIAutomationClient.dll)

public class ExpandCollapsePattern : BasePattern

The ExpandCollapsePattern type exposes the following members.

Public propertyCachedGets the cached UI Automation property values for this ExpandCollapsePattern.
Public propertyCurrentGets the current UI Automation property values for this ExpandCollapsePattern.

Public methodCollapseHides all descendant nodes, controls, or content of the AutomationElement.
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Public methodExpandDisplays all child nodes, controls, or content of the AutomationElement.
Protected methodFinalizeFrees resources and performs other cleanup operations before the object is reclaimed by garbage collection. (Inherited from BasePattern.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Public fieldStatic memberExpandCollapseStatePropertyIdentifies the ExpandCollapseState property.
Public fieldStatic memberPatternIdentifies the ExpandCollapsePattern control pattern.

Aggregate controls—built with child objects that provide the UI for expand/collapse functionality—must support the ExpandCollapsePattern control pattern while their child elements do not. For example, a combo box control is built with a combination of list box, button, and edit controls, but it is only the parent combo box that must support the ExpandCollapsePattern.


A menu control, even though an aggregate of individual menu items, is an exception to this rule. The menu items support the ExpandCollapsePattern control pattern, but the parent menu control does not. A similar exception applies to the tree and tree item controls.

.NET Framework

Supported in: 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.