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AutomationElement.Cached Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Windows.Automation
Assembly:
UIAutomationClient.dll

Ottiene i valori della proprietà Automazione interfaccia utente memorizzati nella cache per questo AutomationElement oggetto.

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

Valore della proprietà

AutomationElement.AutomationElementInformation

Struttura che contiene i valori della proprietà memorizzati nella cache per l'oggetto AutomationElement.

Eccezioni

InvalidOperationException

Nessuna proprietà memorizzata nella cache.

ElementNotAvailableException

L'interfaccia utente per AutomationElement non esiste più.

Esempio

Nell'esempio seguente viene illustrato come memorizzare nella cache la Name proprietà e quindi recuperata tramite la Cached proprietà .

/// <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

Commenti

Le funzioni di accesso per Automazione interfaccia utente proprietà sono rappresentate come proprietà della struttura restituita da Cached. Non è necessario recuperare la struttura; è possibile accedere direttamente ai relativi membri, come nell'esempio seguente. Per informazioni specifiche sulle proprietà disponibili e sul relativo uso, vedere AutomationElement.AutomationElementInformation.

Per ottenere il valore corrente di Automazione interfaccia utente proprietà in questo elemento, utilizzare la Current proprietà .

Si applica a

Vedi anche