AutomationElement.Cached Propiedad

Referencia

Definición

Espacio de nombres:: System.Windows.Automation

Ensamblado:: UIAutomationClient.dll

Importante

Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.

Obtiene los valores de propiedad Automatización de la interfaz de usuario almacenados en caché para este AutomationElement objeto.

public:
 property System::Windows::Automation::AutomationElement::AutomationElementInformation Cached { System::Windows::Automation::AutomationElement::AutomationElementInformation get(); };

public System.Windows.Automation.AutomationElement.AutomationElementInformation Cached { get; }

member this.Cached : System.Windows.Automation.AutomationElement.AutomationElementInformation

Public ReadOnly Property Cached As AutomationElement.AutomationElementInformation

Valor de propiedad

AutomationElement.AutomationElementInformation

Estructura que contiene los valores de propiedades almacenados en caché para AutomationElement.

Excepciones

InvalidOperationException

No hay ninguna propiedad almacenada en memoria caché.

ElementNotAvailableException

La interfaz de usuario para el AutomationElement ya no existe.

Ejemplos

En el ejemplo siguiente se muestra cómo se puede almacenar en caché la Name propiedad y, a continuación, recuperarla mediante la Cached propiedad .

/// <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>
void CachePropertiesWithScope(AutomationElement elementMain)
{
    AutomationElement elementList;

    // Set up the CacheRequest.
    CacheRequest cacheRequest = new CacheRequest();
    cacheRequest.Add(AutomationElement.NameProperty);
    cacheRequest.TreeScope = TreeScope.Element | 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.
        Condition cond = new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.List);
        elementList = elementMain.FindFirst(TreeScope.Children, cond);
    }
    if (elementList == null) return;

    // The following illustrates that the children of the list are in the cache.
    foreach (AutomationElement listItem in elementList.CachedChildren)
    {
        Console.WriteLine(listItem.Cached.Name);
    }

    // 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.
    AutomationElement child = elementList.CachedChildren[0];
    Console.WriteLine(child.CachedParent.Cached.Name);
}

''' <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

Comentarios

Los descriptores de acceso de Automatización de la interfaz de usuario propiedades se representan como propiedades de la estructura devuelta por Cached. No es necesario recuperar la estructura; Puede acceder a sus miembros directamente, como en el ejemplo siguiente. Para obtener información específica sobre las propiedades disponibles y su uso, vea AutomationElement.AutomationElementInformation.

Para obtener el valor actual de Automatización de la interfaz de usuario propiedades en este elemento, use la Current propiedad .

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