UIElement.CaptureMouse 方法

定義

命名空間:

System.Windows

組件:

PresentationCore.dll

嘗試強制將滑鼠的捕捉給這個項目。

public:
 virtual bool CaptureMouse();

public bool CaptureMouse ();

abstract member CaptureMouse : unit -> bool
override this.CaptureMouse : unit -> bool

Public Function CaptureMouse () As Boolean

傳回

Boolean

如果成功捕捉到滑鼠則為 true，否則為 false。

實作

CaptureMouse()

範例

下列範例會實作一對滑鼠和按鍵輸入組合的處理常式，以擷取 (和取消擷取) 滑鼠，並啟用特殊的滑鼠模式來檢視 3D 模型。

private void MouseDownHandler(object sender, MouseButtonEventArgs e)
{
    if (!Enabled) return;
    e.Handled = true;

    if (Keyboard.IsKeyDown(Key.F1) == true)
    {
        Reset();
        return;
    }

    UIElement el = (UIElement)sender;
    _point = e.MouseDevice.GetPosition(el);
    // Initialize the center of rotation to the lookatpoint
    if (!_centered)
    {
        ProjectionCamera camera = (ProjectionCamera)_slaves[0].Camera;
        _center = camera.LookDirection;
        _centered = true;
    }

    _scaling = (e.MiddleButton == MouseButtonState.Pressed);

    if (Keyboard.IsKeyDown(Key.Space) == false)
        _rotating = true;
    else
        _rotating = false;

    el.CaptureMouse();
}

private void MouseUpHandler(object sender, MouseButtonEventArgs e)
{
    if (!_enabled) return;
    e.Handled = true;

    // Stuff the current initial + delta into initial so when we next move we
    // start at the right place.
    if (_rotating == true)
    {
        _rotation = _rotationDelta * _rotation;
    }
    else
    {
        _translate += _translateDelta;
        _translateDelta.X = 0;
        _translateDelta.Y = 0;
    }

    //_scale = _scaleDelta*_scale;
    UIElement el = (UIElement)sender;
    el.ReleaseMouseCapture();
}

Private Sub MouseDownHandler(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    If Not Enabled Then
        Return
    End If
    e.Handled = True


    If Keyboard.IsKeyDown(Key.F1) = True Then
        Reset()
        Return
    End If

    Dim el As UIElement = CType(sender, UIElement)
    _point = e.MouseDevice.GetPosition(el)
    ' Initialize the center of rotation to the lookatpoint
    If Not _centered Then
        Dim camera As ProjectionCamera = CType(_slaves(0).Camera, ProjectionCamera)
        _center = camera.LookDirection
        _centered = True
    End If

    _scaling = (e.MiddleButton = MouseButtonState.Pressed)

    If Keyboard.IsKeyDown(Key.Space) = False Then
        _rotating = True
    Else
        _rotating = False
    End If

    el.CaptureMouse()
End Sub

Private Sub MouseUpHandler(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    If Not _enabled Then
        Return
    End If
    e.Handled = True

    ' Stuff the current initial + delta into initial so when we next move we
    ' start at the right place.
    If _rotating = True Then
        _rotation = _rotationDelta * _rotation
    Else
        _translate += _translateDelta
        _translateDelta.X = 0
        _translateDelta.Y = 0
    End If

    '_scale = _scaleDelta * _scale
    Dim el As UIElement = CType(sender, UIElement)
    el.ReleaseMouseCapture()
End Sub

備註

若要擷取，必須啟用專案。 在呼叫 CaptureMouse 之前，請檢查 是否 IsEnabledtrue 為 。

如果呼叫 CaptureMouse 傳 true 回 ，則 IsMouseCaptured 也是 true 。

如果呼叫 CaptureMouse 傳 true 回 ，則會 GotMouseCapture 引發 和 IsMouseCapturedChanged 事件， RoutedEventArgs.Source 並在事件資料中報告為呼叫 方法的專案 CaptureMouse 。 如果您強制擷取，您可能會干擾現有的擷取，特別是與滑鼠拖放相關的擷取。

若要清除所有元素的滑鼠擷取，請使用提供做為 null 的參數 element 呼叫 Mouse.Capture 。

另請參閱

• IsMouseCaptured