VisualTreeHelper.HitTest Methode

public:
 static System::Windows::Media::HitTestResult ^ HitTest(System::Windows::Media::Visual ^ reference, System::Windows::Point point);

public static System.Windows.Media.HitTestResult HitTest (System.Windows.Media.Visual reference, System.Windows.Point point);

static member HitTest : System.Windows.Media.Visual * System.Windows.Point -> System.Windows.Media.HitTestResult

Public Shared Function HitTest (reference As Visual, point As Point) As HitTestResult

Parameter

Gibt zurück

HitTestResult

Das als HitTestResult-Typ zurückgegebene Ergebnis des Treffertests für das Visual-Element.

Beispiele

Im folgenden Beispiel wird gezeigt, wie Sie die Methode verwenden, um die HitTest Objekte innerhalb eines CanvasObjekts zu testen.

// Respond to the left mouse button down event by initiating the hit test.
private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    // Retrieve the coordinate of the mouse position.
    Point pt = e.GetPosition((UIElement)sender);

    // Perform the hit test against a given portion of the visual object tree.
    HitTestResult result = VisualTreeHelper.HitTest(myCanvas, pt);

    if (result != null)
    {
        // Perform action on hit visual object.
    }
}

' Respond to the left mouse button down event by initiating the hit test.
Private Overloads Sub OnMouseLeftButtonDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    ' Retrieve the coordinate of the mouse position.
    Dim pt As Point = e.GetPosition(CType(sender, UIElement))

    ' Perform the hit test against a given portion of the visual object tree.
    Dim result As HitTestResult = VisualTreeHelper.HitTest(myCanvas, pt)

    If result IsNot Nothing Then
        ' Perform action on hit visual object.
    End If
End Sub

Hinweise

Die VisualHit Eigenschaft des Rückgabewerts stellt das Visual Objekt dar, das getroffen wurde.

Siehe auch

• Beispiel für Treffertests mit DarwingVisuals

public:
 static void HitTest(System::Windows::Media::Media3D::Visual3D ^ reference, System::Windows::Media::HitTestFilterCallback ^ filterCallback, System::Windows::Media::HitTestResultCallback ^ resultCallback, System::Windows::Media::Media3D::HitTestParameters3D ^ hitTestParameters);

public static void HitTest (System.Windows.Media.Media3D.Visual3D reference, System.Windows.Media.HitTestFilterCallback filterCallback, System.Windows.Media.HitTestResultCallback resultCallback, System.Windows.Media.Media3D.HitTestParameters3D hitTestParameters);

static member HitTest : System.Windows.Media.Media3D.Visual3D * System.Windows.Media.HitTestFilterCallback * System.Windows.Media.HitTestResultCallback * System.Windows.Media.Media3D.HitTestParameters3D -> unit

Public Shared Sub HitTest (reference As Visual3D, filterCallback As HitTestFilterCallback, resultCallback As HitTestResultCallback, hitTestParameters As HitTestParameters3D)

Parameter

Hinweise

Der filterCallback Parameter kann in diesem Fall ignoriert werden null. Wenn filterCallback nicht null, wird es vor resultCallbackdem Aufruf aufgerufen. resultCallback darf nicht null sein.

public:
 static void HitTest(System::Windows::Media::Visual ^ reference, System::Windows::Media::HitTestFilterCallback ^ filterCallback, System::Windows::Media::HitTestResultCallback ^ resultCallback, System::Windows::Media::HitTestParameters ^ hitTestParameters);

public static void HitTest (System.Windows.Media.Visual reference, System.Windows.Media.HitTestFilterCallback filterCallback, System.Windows.Media.HitTestResultCallback resultCallback, System.Windows.Media.HitTestParameters hitTestParameters);

static member HitTest : System.Windows.Media.Visual * System.Windows.Media.HitTestFilterCallback * System.Windows.Media.HitTestResultCallback * System.Windows.Media.HitTestParameters -> unit

Public Shared Sub HitTest (reference As Visual, filterCallback As HitTestFilterCallback, resultCallback As HitTestResultCallback, hitTestParameters As HitTestParameters)

Parameter

Beispiele

Im folgenden Beispiel wird gezeigt, wie Sie die Methode verwenden, um die HitTest Objekte innerhalb eines CanvasObjekts zu testen.

// Respond to the right mouse button down event by setting up a hit test results callback.
private void OnMouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
    // Retrieve the coordinate of the mouse position.
    Point pt = e.GetPosition((UIElement)sender);

    // Clear the contents of the list used for hit test results.
    hitResultsList.Clear();

    // Set up a callback to receive the hit test result enumeration.
    VisualTreeHelper.HitTest(myCanvas, null,
        new HitTestResultCallback(MyHitTestResult),
        new PointHitTestParameters(pt));

    // Perform actions on the hit test results list.
    if (hitResultsList.Count > 0)
    {
        Console.WriteLine("Number of Visuals Hit: " + hitResultsList.Count);
    }
}

' Respond to the right mouse button down event by setting up a hit test results callback.
Private Overloads Sub OnMouseRightButtonDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    ' Retrieve the coordinate of the mouse position.
    Dim pt As Point = e.GetPosition(CType(sender, UIElement))

    ' Clear the contents of the list used for hit test results.
    hitResultsList.Clear()

    ' Set up a callback to receive the hit test result enumeration.
    VisualTreeHelper.HitTest(myCanvas, Nothing, New HitTestResultCallback(AddressOf MyHitTestResult), New PointHitTestParameters(pt))

    ' Perform actions on the hit test results list.
    If hitResultsList.Count > 0 Then
        Console.WriteLine("Number of Visuals Hit: " & hitResultsList.Count)
    End If
End Sub

// Return the result of the hit test to the callback.
public HitTestResultBehavior MyHitTestResult(HitTestResult result)
{
    // Add the hit test result to the list that will be processed after the enumeration.
    hitResultsList.Add(result.VisualHit);

    // Set the behavior to return visuals at all z-order levels.
    return HitTestResultBehavior.Continue;
}

' Return the result of the hit test to the callback.
Public Function MyHitTestResult(ByVal result As HitTestResult) As HitTestResultBehavior
    ' Add the hit test result to the list that will be processed after the enumeration.
    hitResultsList.Add(result.VisualHit)

    ' Set the behavior to return visuals at all z-order levels.
    Return HitTestResultBehavior.Continue
End Function

Hinweise

Der filterCallback Parameter kann in diesem Fall ignoriert werden null. Wenn filterCallback nicht null, wird es vor resultCallbackdem Aufruf aufgerufen. resultCallback darf nicht null sein.

Siehe auch

• Beispiel für Treffertests mit DarwingVisuals