InkOverlay.StrokesDeleting 事件

项目
11/04/2008

在从 Ink 属性删除笔画之前发生。

命名空间： Microsoft.Ink
程序集： Microsoft.Ink（在 Microsoft.Ink.dll 中）

语法

声明
Public Event StrokesDeleting As InkOverlayStrokesDeletingEventHandler
用法
Dim instance As InkOverlay
Dim handler As InkOverlayStrokesDeletingEventHandler

AddHandler instance.StrokesDeleting, handler

public event InkOverlayStrokesDeletingEventHandler StrokesDeleting

public:
 event InkOverlayStrokesDeletingEventHandler^ StrokesDeleting {
    void add (InkOverlayStrokesDeletingEventHandler^ value);
    void remove (InkOverlayStrokesDeletingEventHandler^ value);
}

/** @event */
public void add_StrokesDeleting (InkOverlayStrokesDeletingEventHandler value)
/** @event */
public void remove_StrokesDeleting (InkOverlayStrokesDeletingEventHandler value)

JScript 不支持事件。

备注

在对附加到 InkOverlay 对象的墨迹调用 Ink.DeleteStroke 或 Ink.DeleteStrokes 方法时激发此事件。

事件处理程序接收 InkOverlayStrokesDeletingEventArgs 类型的参数，该参数包含有关此事件的数据。

创建 InkOverlayStrokesDeletingEventHandler 委托时，需要标识将处理该事件的方法。若要将该事件与事件处理程序关联，请将该委托的一个实例添加到事件中。除非移除了该委托，否则每当发生该事件时就会调用此事件处理程序。出于性能方面的原因，默认事件关注处于关闭状态，但如果添加事件处理程序，它将自动打开。

示例

此示例演示如何订阅 StrokesDeleting 事件，以使您能够还原最后一个删除的笔画。

激发 StrokesDeleting 事件时，将保存即将删除的 Stroke 对象。

Private Sub mInkObject_StrokesDeleting(ByVal sender As Object, ByVal e As InkOverlayStrokesDeletingEventArgs)
    ' Store strokes for later undo. They must be stored in
    ' a separate Ink object. 
    mInkDeleted = New Ink()
    mInkDeleted.AddStrokesAtRectangle(e.StrokesToDelete, e.StrokesToDelete.GetBoundingBox())
End Sub

private void mInkObject_StrokesDeleting(object sender, InkOverlayStrokesDeletingEventArgs e)
{
    // Store strokes for later undo. They must be stored in
    // a separate Ink object. 
    mInkDeleted = new Ink();
    mInkDeleted.AddStrokesAtRectangle(e.StrokesToDelete, e.StrokesToDelete.GetBoundingBox());
}

为响应用户操作（比如单击 MenuItem），以前删除的 Stroke 对象将添加回原始 Ink 对象。

If Not mInkDeleted Is Nothing Then
    ' Add strokes back.  (You need to use Ink.AddStrokesAtRectangle as opposed
    ' to Strokes.Add because you are dealing with two different Ink objects.)
    mInkObject.Ink.AddStrokesAtRectangle(mInkDeleted.Strokes, mInkDeleted.Strokes.GetBoundingBox())
    mInkDeleted = Nothing
    ' For best performance, you should Invalidate the rectangle created by the 
    ' bounding box (converted from ink space to pixel space).  For simplicity,
    ' we will just refresh the entire control.
    Refresh()
End If

if (mInkDeleted != null)
{
    // Add strokes back.  (You need to use Ink.AddStrokesAtRectangle as opposed
    // to Strokes.Add because you are dealing with two different Ink objects.)
    mInkObject.Ink.AddStrokesAtRectangle(mInkDeleted.Strokes, mInkDeleted.Strokes.GetBoundingBox());
    mInkDeleted = null;
    // For best performance, you should Invalidate the rectangle created by the 
    // bounding box (converted from ink space to pixel space).  For simplicity,
    // we will just refresh the entire control.
    Refresh();
}