InkPicture.CursorDown 事件

發行項
10/29/2008

當游標筆尖接觸到數位手寫板表面時發生。

命名空間： Microsoft.Ink
組件： Microsoft.Ink (在 Microsoft.Ink.dll 中)

語法

'宣告
Public Event CursorDown As InkCollectorCursorDownEventHandler
'用途
Dim instance As InkPicture
Dim handler As InkCollectorCursorDownEventHandler

AddHandler instance.CursorDown, handler

public event InkCollectorCursorDownEventHandler CursorDown

public:
 event InkCollectorCursorDownEventHandler^ CursorDown {
    void add (InkCollectorCursorDownEventHandler^ value);
    void remove (InkCollectorCursorDownEventHandler^ value);
}

/** @event */
public void add_CursorDown (InkCollectorCursorDownEventHandler value)
/** @event */
public void remove_CursorDown (InkCollectorCursorDownEventHandler value)

JScript 不支援事件。

備註

事件處理常式會接收 InkCollectorCursorDownEventArgs 型別的引數，其中包含這個事件的相關資料。

在建立 InkCollectorCursorDownEventHandler 委派時，您要識別處理事件的方法。若要使事件與您的事件處理常式產生關聯，請將委派的執行個體加入至事件。除非您移除委派，否則每當事件發生時就會呼叫事件處理常式。基於效能考量，相關事件的預設是關閉的，但會在您加入事件處理常式時自動開啟。

如果事件處理常式中執行太多程式碼，則這個事件可能對筆墨效能造成負面影響。若要改善即時筆墨效能，請在使用筆墨書寫時隱藏滑鼠游標。若要執行這項操作，請在 MouseDown 事件處理常式中隱藏滑鼠游標，並且在 MouseUp 事件處理常式中顯示滑鼠游標。

範例

這個範例會示範如何訂閱 CursorDown 事件和 Stroke 事件，計算使用者建立筆劃所需的時間長度。

筆劃開始時，會引發 CursorDown 事件。目前的時間會放入 Stroke 物件的 ExtendedProperties 集合。

Private Sub mInkObject_CursorDown(ByVal sender As Object, ByVal e As InkCollectorCursorDownEventArgs)
    ' add extended property indicating the time the stroke started
    ' STROKE_START_GUID is class level string via GUID generator
    e.Stroke.ExtendedProperties.Add(New Guid(STROKE_START_GUID), DateTime.Now)
End Sub

private void mInkObject_CursorDown(object sender, InkCollectorCursorDownEventArgs e)
{
    // add extended property indicating the time the stroke started
    // STROKE_START_GUID is class level string via GUID generator
    e.Stroke.ExtendedProperties.Add(new Guid(STROKE_START_GUID), DateTime.Now);
}

筆劃完成時，會引發 Stroke 事件。開始時間是擷取自 Stroke 物件的 ExtendedProperties 集合，並且用來計算經過的時間。

Private Sub mInkObject_Stroke1(ByVal sender As Object, ByVal e As InkCollectorStrokeEventArgs)
    ' check to see if extended property for start time exists
    ' Attempting to access an extended property that hasn't been created throws an exception
    ' STROKE_START_GUID is class level string via GUID generator
    If (e.Stroke.ExtendedProperties.DoesPropertyExist(New Guid(STROKE_START_GUID))) Then

        Dim startTime As DateTime = DirectCast(e.Stroke.ExtendedProperties(New Guid(STROKE_START_GUID)).Data, DateTime)
        Dim endTime As DateTime = DateTime.Now
        Dim span As TimeSpan = New TimeSpan(endTime.Ticks - startTime.Ticks)

        ' add extended property indicating the time the stroke ended
        ' STROKE_END_GUID is class level string via GUID generator
        e.Stroke.ExtendedProperties.Add(New Guid(STROKE_END_GUID), endTime)

        ' display the number of seconds in creating this stroke
        Me.statusLabelStrokeTime.Text = span.TotalSeconds.ToString()
    End If
End Sub

private void mInkObject_Stroke1(object sender, InkCollectorStrokeEventArgs e)
{
    // check to see if extended property for start time exists
    // Attempting to access an extended property that hasn't been created throws an exception
    // STROKE_START_GUID is class level string via GUID generator
    if (e.Stroke.ExtendedProperties.DoesPropertyExist(new Guid(STROKE_START_GUID)))
    {
        DateTime startTime = (DateTime)e.Stroke.ExtendedProperties[new Guid(STROKE_START_GUID)].Data;
        DateTime endTime = DateTime.Now;
        TimeSpan span = new TimeSpan(endTime.Ticks - startTime.Ticks);

        // add extended property indicating the time the stroke ended
        // STROKE_END_GUID is class level string via GUID generator
        e.Stroke.ExtendedProperties.Add(new Guid(STROKE_END_GUID), endTime);

        // display the number of seconds in creating this stroke
        this.statusLabelStrokeTime.Text = span.TotalSeconds.ToString();
    }
}