Нахождение Элемента Автоматизации Пользовательского Интерфейса в Зависимости от Состояния Свойства

Примечание.

Эта документация предназначена для разработчиков .NET Framework, желающих использовать управляемые классы автоматизации пользовательского интерфейса, определенные в пространстве имен System.Windows.Automation. Последние сведения об автоматизации пользовательского интерфейса см. в статье API автоматизации Windows. Автоматизация пользовательского интерфейса.

В этой статье приведен пример кода, в котором показано, как найти элемент в дереве автоматизации пользовательского интерфейса на основе определенного свойства или свойств.

Пример

В приведенном ниже примере указывается ряд условий свойств, определяющих нужный элемент (или элементы) в дереве AutomationElement. Затем выполняется поиск всех соответствующих элементов с помощью метода FindAll, включающего ряд логических операций AndCondition, которые ограничивают количество соответствующих элементов.

Примечание.

При выполнении поиска на основе RootElement следует пытаться получить только прямые дочерние элементы. Поиск потомков может выполнять итерацию по сотням или даже тысячам элементов, что может привести к переполнению стека. Если вы пытаетесь получить определенный элемент на более низком уровне, необходимо запустить поиск из окна приложения или из контейнера на более низком уровне.

///--------------------------------------------------------------------
/// <summary>
/// Walks the UI Automation tree of the target and reports the control
/// type of each element it finds in the control view to the client.
/// </summary>
/// <param name="targetTreeViewElement">
/// The root of the search on this iteration.
/// </param>
/// <param name="elementIndex">
/// The TreeView index for this iteration.
/// </param>
/// <remarks>
/// This is a recursive function that maps out the structure of the
/// subtree of the target beginning at the AutomationElement passed in
/// as the rootElement on the first call. This could be, for example,
/// an application window.
/// CAUTION: Do not pass in AutomationElement.RootElement. Attempting
/// to map out the entire subtree of the desktop could take a very
/// long time and even lead to a stack overflow.
/// </remarks>
///--------------------------------------------------------------------
private void FindTreeViewDescendants(
    AutomationElement targetTreeViewElement, int treeviewIndex)
{
    if (targetTreeViewElement == null)
        return;

    AutomationElement elementNode =
        TreeWalker.ControlViewWalker.GetFirstChild(targetTreeViewElement);

    while (elementNode != null)
    {
        Label elementInfo = new Label();
        elementInfo.Margin = new Thickness(0);
        clientTreeViews[treeviewIndex].Children.Add(elementInfo);

        // Compile information about the control.
        elementInfoCompile = new StringBuilder();
        string controlName =
            (elementNode.Current.Name == "") ?
            "Unnamed control" : elementNode.Current.Name;
        string autoIdName =
            (elementNode.Current.AutomationId == "") ?
            "No AutomationID" : elementNode.Current.AutomationId;

        elementInfoCompile.Append(controlName)
            .Append(" (")
            .Append(elementNode.Current.ControlType.LocalizedControlType)
            .Append(" - ")
            .Append(autoIdName)
            .Append(")");

        // Test for the control patterns of interest for this sample.
        object objPattern;
        ExpandCollapsePattern expcolPattern;
        if (true == elementNode.TryGetCurrentPattern(ExpandCollapsePattern.Pattern, out objPattern))
        {
            expcolPattern = objPattern as ExpandCollapsePattern;
            if (expcolPattern.Current.ExpandCollapseState != ExpandCollapseState.LeafNode)
            {
                Button expcolButton = new Button();
                expcolButton.Margin = new Thickness(0, 0, 0, 5);
                expcolButton.Height = 20;
                expcolButton.Width = 100;
                expcolButton.Content = "ExpandCollapse";
                expcolButton.Tag = expcolPattern;
                expcolButton.Click +=
                    new RoutedEventHandler(ExpandCollapse_Click);
                clientTreeViews[treeviewIndex].Children.Add(expcolButton);
            }
        }
        TogglePattern togPattern;
        if (true == elementNode.TryGetCurrentPattern(TogglePattern.Pattern, out objPattern))
        {
            togPattern = objPattern as TogglePattern;
            Button togButton = new Button();
            togButton.Margin = new Thickness(0, 0, 0, 5);
            togButton.Height = 20;
            togButton.Width = 100;
            togButton.Content = "Toggle";
            togButton.Tag = togPattern;
            togButton.Click += new RoutedEventHandler(Toggle_Click);
            clientTreeViews[treeviewIndex].Children.Add(togButton);
        }
        InvokePattern invPattern;
        if (true == elementNode.TryGetCurrentPattern(InvokePattern.Pattern, out objPattern))
        {
            invPattern = objPattern as InvokePattern;
            Button invButton = new Button();
            invButton.Margin = new Thickness(0);
            invButton.Height = 20;
            invButton.Width = 100;
            invButton.Content = "Invoke";
            invButton.Tag = invPattern;
            invButton.Click += new RoutedEventHandler(Invoke_Click);
            clientTreeViews[treeviewIndex].Children.Add(invButton);
        }
        // Display compiled information about the control.
        elementInfo.Content = elementInfoCompile;
        Separator sep = new Separator();
        clientTreeViews[treeviewIndex].Children.Add(sep);

        // Iterate to next element.
        // elementNode - Current element.
        // treeviewIndex - Index of parent TreeView.
        FindTreeViewDescendants(elementNode, treeviewIndex);
        elementNode =
            TreeWalker.ControlViewWalker.GetNextSibling(elementNode);
    }
}
'''--------------------------------------------------------------------
''' <summary>
''' Walks the UI Automation tree of the target and reports the control 
''' type of each element it finds in the control view to the client.
''' </summary>
''' <param name="targetTreeViewElement">
''' The root of the search on this iteration.
''' </param>
''' <param name="treeviewIndex">
''' The TreeView index for this iteration.
''' </param>
''' <remarks>
''' This is a recursive function that maps out the structure of the 
''' subtree beginning at the AutomationElement passed in as 
''' rootElement on the first call. This could be, for example,
''' an application window.
''' CAUTION: Do not pass in AutomationElement.RootElement. Attempting 
''' to map out the entire subtree of the desktop could take a very 
''' long time and even lead to a stack overflow.
''' </remarks>
'''--------------------------------------------------------------------
Private Sub FindTreeViewDescendants( _
ByVal targetTreeViewElement As AutomationElement, _
ByVal treeviewIndex As Integer)
    If (IsNothing(targetTreeViewElement)) Then
        Return
    End If

    Dim elementNode As AutomationElement = _
    TreeWalker.ControlViewWalker.GetFirstChild(targetTreeViewElement)

    While Not (elementNode Is Nothing)
        Dim elementInfo As New Label()
        elementInfo.Margin = New Thickness(0)
        clientTreeViews(treeviewIndex).Children.Add(elementInfo)

        ' Compile information about the control.
        elementInfoCompile = New StringBuilder()
        Dim controlName As String
        If (elementNode.Current.Name = "") Then
            controlName = "Unnamed control"
        Else
            controlName = elementNode.Current.Name
        End If
        Dim autoIdName As String
        If (elementNode.Current.AutomationId = "") Then
            autoIdName = "No AutomationID"
        Else
            autoIdName = elementNode.Current.AutomationId
        End If


        elementInfoCompile.Append(controlName).Append(" (") _
        .Append(elementNode.Current.ControlType.LocalizedControlType) _
        .Append(" - ").Append(autoIdName).Append(")")

        ' Test for the control patterns of interest for this sample.
        Dim objPattern As Object = Nothing
        Dim expcolPattern As ExpandCollapsePattern
        If True = elementNode.TryGetCurrentPattern(ExpandCollapsePattern.Pattern, objPattern) Then
            expcolPattern = DirectCast(objPattern, ExpandCollapsePattern)
            If expcolPattern.Current.ExpandCollapseState <> ExpandCollapseState.LeafNode Then
                Dim expcolButton As New Button()
                expcolButton.Margin = New Thickness(0, 0, 0, 5)
                expcolButton.Height = 20
                expcolButton.Width = 100
                expcolButton.Content = "ExpandCollapse"
                expcolButton.Tag = expcolPattern
                AddHandler expcolButton.Click, AddressOf ExpandCollapse_Click
                clientTreeViews(treeviewIndex).Children.Add(expcolButton)
            End If
        End If
        Dim togPattern As TogglePattern
        If True = elementNode.TryGetCurrentPattern(TogglePattern.Pattern, objPattern) Then
            togPattern = DirectCast(objPattern, TogglePattern)
            Dim togButton As New Button()
            togButton.Margin = New Thickness(0, 0, 0, 5)
            togButton.Height = 20
            togButton.Width = 100
            togButton.Content = "Toggle"
            togButton.Tag = togPattern
            AddHandler togButton.Click, AddressOf Toggle_Click
            clientTreeViews(treeviewIndex).Children.Add(togButton)
        End If
        Dim invPattern As InvokePattern
        If True = elementNode.TryGetCurrentPattern(InvokePattern.Pattern, objPattern) Then
            invPattern = DirectCast(objPattern, InvokePattern)
            Dim invButton As New Button()
            invButton.Margin = New Thickness(0)
            invButton.Height = 20
            invButton.Width = 100
            invButton.Content = "Invoke"
            invButton.Tag = invPattern
            AddHandler invButton.Click, AddressOf Invoke_Click
            clientTreeViews(treeviewIndex).Children.Add(invButton)
        End If
        ' Display compiled information about the control.
        elementInfo.Content = elementInfoCompile
        Dim sep As New Separator()
        clientTreeViews(treeviewIndex).Children.Add(sep)

        ' Iterate to next element.
        ' elementNode - Current element.
        ' treeviewIndex - Index of parent TreeView.
        FindTreeViewDescendants(elementNode, treeviewIndex)
        elementNode = TreeWalker.ControlViewWalker.GetNextSibling(elementNode)
    End While

End Sub

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