为什么用下面的代码绘出来的图一闪就没有了Private Sub Button1_Click(ByVal sender As Systemobject, ByVal e As System.EventArgs)Hardles Button1.Click DrawALine(PageToShow,Color.Red,50, 50,5,100) End Sub”以下建立绘图函数 Public sub DrawALine(ByVal WhereToraw as Picture,ByVal Draw_Color As Color, ByVal StartPoint_X As Integer,ByVal StartPoint Y As Integer, ByVal Line_Width As Integer, ByVal Line_Height As Integer) Dim Pic As New PictureBox With Pic.Name ="Pic".Size = New Size(Line_Width+ 6, Line_Height + 6) .SizeMode = PictureBoxSizemode.StretchImage.Parent = WhereToDraw.Location= New PointStartPoint_x-3 StartPoint_Y-3) End With Dim g As Graphics=Pic.CreateGraphics Dim Draw_Pen As New Pen(Draw_color, Line Width)g.DrawLine (Draw_Pen, 3 3,3+ Line_Width, 3 + Line_Height) Ernd Sub