InkCanvas.SelectionChanged 事件

定义

命名空间:

System.Windows.Controls

程序集:

PresentationFramework.dll

在 InkCanvas 上的选择更改时发生。

public:
 event EventHandler ^ SelectionChanged;

public event EventHandler SelectionChanged;

member this.SelectionChanged : EventHandler 

Public Custom Event SelectionChanged As EventHandler 

事件类型

EventHandler

示例

以下示例阻止用户进行小于其原始大小的选择。

Rect selectionBounds;

// Don't allow the user to make the selection smaller than its original size.
void inkCanvas1_SelectionResizing(object sender, InkCanvasSelectionEditingEventArgs e)
{
    if (selectionBounds == null || selectionBounds.IsEmpty)
    {
        return;
    }

    double resizeHeight;
    double resizeWidth;

    // If the user made the height of the selection smaller, 
    // use the selection's original height.
    if (e.NewRectangle.Height < selectionBounds.Height)
    {
        resizeHeight = selectionBounds.Height;
    }
    else
    {
        resizeHeight = e.NewRectangle.Height;
    }

    // If the user made the width of the selection smaller, 
    // use the selection's original width.
    if (e.NewRectangle.Width < selectionBounds.Width)
    {
        resizeWidth = selectionBounds.Width;
    }
    else
    {
        resizeWidth = e.NewRectangle.Width;
    }

    // Create a the new rectangle with the appropriate width and height.
    e.NewRectangle = new Rect(e.NewRectangle.X, e.NewRectangle.Y, resizeWidth, resizeHeight);
}

// Keep track of the selection bounds.
void inkCanvas1_SelectionChanged(object sender, EventArgs e)
{
    selectionBounds = inkCanvas1.GetSelectionBounds();
}

Private selectionBounds As Rect

' Don't allow the user to make the selection smaller than its original size.
Private Sub inkCanvas1_SelectionResizing(ByVal sender As Object, ByVal e As InkCanvasSelectionEditingEventArgs)

    If selectionBounds.IsEmpty Then
        Return
    End If

    Dim resizeHeight As Double
    Dim resizeWidth As Double

    ' If the user made the height of the selection smaller, 
    ' use the selection's original height.
    If e.NewRectangle.Height < selectionBounds.Height Then
        resizeHeight = selectionBounds.Height
    Else
        resizeHeight = e.NewRectangle.Height
    End If

    ' If the user made the width of the selection smaller, 
    ' use the selection's original width.
    If e.NewRectangle.Width < selectionBounds.Width Then
        resizeWidth = selectionBounds.Width
    Else
        resizeWidth = e.NewRectangle.Width
    End If

    ' Create a the new rectangle with the appropriate width and height.
    e.NewRectangle = New Rect(e.NewRectangle.X, e.NewRectangle.Y, resizeWidth, resizeHeight)

End Sub


' Keep track of the selection bounds.
Private Sub inkCanvas1_SelectionChanged(ByVal sender As Object, ByVal e As EventArgs)

    selectionBounds = inkCanvas1.GetSelectionBounds()

End Sub

注解

当用户选择并应用一组墨迹笔划和/或元素后，将引发此事件。

如果必须在应用所选内容之前处理选择一组墨迹笔划和/或元素的请求，请将事件处理程序添加到事件 SelectionChanging 。

另请参阅

• SelectionChanging
• GetSelectedStrokes()
• GetSelectedElements()