UIElement.CaptureMouse 方法

定義

嘗試強制將滑鼠的捕捉給這個項目。Attempts to force capture of the mouse to this element.

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 falsetrue if the mouse is successfully captured; otherwise, false.

實作

範例

下列範例會針對滑鼠和按鍵輸入組合來實行一組處理常式,以捕捉 (和 uncapture) 滑鼠,並啟用特殊的滑鼠模式來觀看3D 模型。The following example implements a pair of handlers for mouse and key input combination that capture (and uncapture) the mouse and enable a special mouse mode for viewing a 3D model.

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

您必須啟用元素才能加以捕捉。To be captured, an element must be enabled. 檢查是否 IsEnabledtrue 呼叫之前 CaptureMouseCheck whether IsEnabled is true before you call CaptureMouse.

如果呼叫 CaptureMouse 傳回 true ,則 IsMouseCaptured 也會傳回 trueIf calling CaptureMouse returns true, then IsMouseCaptured is also true.

如果呼叫 CaptureMouse 傳回 true ,則 GotMouseCapture IsMouseCapturedChanged 會引發和事件,並將 RoutedEventArgs.Source 事件資料回報為 CaptureMouse 呼叫方法的元素。If calling CaptureMouse returns true, then the GotMouseCapture and IsMouseCapturedChanged events are raised, with RoutedEventArgs.Source in the event data reported as the element where the CaptureMouse method is called. 如果您強制捕捉,您可能會干擾現有的捕捉,特別是與滑鼠拖放相關的捕捉。If you force capture, you might interfere with existing captures - especially with captures that relate to drag-and-drop with the mouse.

若要清除所有元素的滑鼠捕捉,請 Mouse.Capture 使用 element 提供的參數來呼叫 nullTo clear mouse capture from all elements, call Mouse.Capture with the element parameter provided as null.

適用於

另請參閱