VB.NET Behavior类代码示例

Class MyGlyph
    Inherits Glyph
    Private control As Control
    Private behaviorSvc As _
        System.Windows.Forms.Design.Behavior.BehaviorService

    Public Sub New(ByVal behaviorSvc As _
        System.Windows.Forms.Design.Behavior.BehaviorService, _
        ByVal control As Control)

        MyBase.New(New MyBehavior())
        Me.behaviorSvc = behaviorSvc
        Me.control = control
    End Sub

    Public Overrides ReadOnly Property Bounds() As Rectangle
        Get
            ' Create a glyph that is 10x10 and sitting
            ' in the middle of the control.  Glyph coordinates
            ' are in adorner window coordinates, so we must map
            ' using the behavior service.
            Dim edge As Point = behaviorSvc.ControlToAdornerWindow(control)
            Dim size As Size = control.Size
            Dim center As New Point(edge.X + size.Width / 2, edge.Y + _
                size.Height / 2)

            Dim bounds1 As New Rectangle(center.X - 5, center.Y - 5, 10, 10)

            Return bounds1
        End Get
    End Property

    Public Overrides Function GetHitTest(ByVal p As Point) As Cursor
        ' GetHitTest is called to see if the point is
        ' within this glyph.  This gives us a chance to decide
        ' what cursor to show.  Returning null from here means
        ' the mouse pointer is not currently inside of the glyph.
        ' Returning a valid cursor here indicates the pointer is
        ' inside the glyph,and also enables our Behavior property
        ' as the active behavior.
        If Bounds.Contains(p) Then
            Return Cursors.Hand
        End If

        Return Nothing

    End Function


    Public Overrides Sub Paint(ByVal pe As PaintEventArgs)
        ' Draw our glyph.  It is simply a blue ellipse.
        pe.Graphics.FillEllipse(Brushes.Blue, Bounds)

    End Sub

    ' By providing our own behavior we can do something interesting
    ' when the user clicks or manipulates our glyph.

    Class MyBehavior
        Inherits System.Windows.Forms.Design.Behavior.Behavior

        Public Overrides Function OnMouseUp(ByVal g As Glyph, _
            ByVal button As MouseButtons) As Boolean
            MessageBox.Show("Hey, you clicked the mouse here")
            Return True
            ' indicating we processed this event.
        End Function 'OnMouseUp
    End Class

End Class