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AutomationElement.Cached Property

Gets the cached UI Automation property values for this AutomationElement object.

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

'Declaration
Public ReadOnly Property Cached As AutomationElement.AutomationElementInformation

Property Value

Type: System.Windows.Automation.AutomationElement.AutomationElementInformation
A structure containing the cached property values for the AutomationElement.

ExceptionCondition
InvalidOperationException

There are no cached properties.

ElementNotAvailableException

The UI for the AutomationElement no longer exists.

The accessors for UI Automation properties are represented as properties of the structure returned by Cached. You do not need to retrieve the structure; you can access its members directly, as in the example below. For specific information on the properties available and their use, see AutomationElement.AutomationElementInformation.

To get the current value of UI Automation properties on this element use the Current property.

The following example shows how the Name property can be cached and then retrieved by using the Cached property.

''' <summary> 
''' Gets a list box element and caches the Name property of its children (the list items). 
''' </summary> 
''' <param name="elementMain">The UI Automation element for the parent window.</param> 
Sub CachePropertiesWithScope(ByVal elementMain As AutomationElement)
    Dim elementList As AutomationElement

    ' Set up the CacheRequest. 
    Dim cacheRequest As New CacheRequest()
    cacheRequest.Add(AutomationElement.NameProperty)
    cacheRequest.TreeScope = TreeScope.Element Or TreeScope.Children

    ' Activate the CacheRequest and get the element. Note that the scope of the CacheRequest 
    ' is in relation to the object being retrieved: the list box and its children are  
    ' cached, not the main window and its children. 
    Using cacheRequest.Activate()
        ' Load the list element and cache the specified properties for its descendants. 
        Dim myCondition As New PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.List)
        elementList = elementMain.FindFirst(TreeScope.Children, myCondition)

        If elementList Is Nothing Then 
            Return 
        End If 

        ' The following illustrates that the children of the list are in the cache. 
        Dim listItem As AutomationElement
        For Each listItem In elementList.CachedChildren
            Console.WriteLine(listItem.Cached.Name)
        Next listItem

        ' The following call raises an exception, because the IsEnabled property was not cached. 
        '** Console.WriteLine(listItem.Cached.IsEnabled) ** 

        ' The following illustrates that because the list box itself was cached, it is now 
        ' available as the CachedParent of each list item. 
        Dim child As AutomationElement = elementList.CachedChildren(0)
        Console.WriteLine(child.CachedParent.Cached.Name)
    End Using 
End Sub 'CachePropertiesWithScope

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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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