WPF 滑鼠座標 ELLIPSE

Dim OldPos, CurPos As Point
Dim cy As Color = Color.FromArgb(255, 255, 255, 0)
Dim Ys As Brush = New SolidColorBrush(cy)

'取得線第一點座標
OldPos = e.GetPosition(Me.Canvas_Draw)


Try
'取得滑鼠按下座標
p1 = e.GetPosition(Me.Canvas_Draw)
'建立一個橢圓物件,繪圓是用橢圓來表示
Dim pt1 = New Ellipse
'設定橢圓的名稱屬性
pt1.SetValue(NameProperty, "pt" + ptNo.ToString())
'設定橢圓的寬度屬性
pt1.SetValue(WidthProperty, 5.0)

'設定橢圓要填滿的顏色
pt1.Fill = Ys
'將元件加入繪圖區裡
Me.Canvas_Draw.Children.Add(pt1)

'顯示點座標資訊
Me.txtInfo.Text = "點" + ptNo.ToString() + "座標X=" + p1.X.ToString() + ",Y=" + p1.Y.ToString()
Catch e1 As Exception
MessageBox.Show("點錯誤" + e1.Message.ToString() & vbCrLf)
End Try