[RESOLVED] Drawn paths won't go away.

I have this code for drawing a path.

Code:

---

        Dim map As New Bitmap(l1.Size.Width, l1.Size.Height, l1.CreateGraphics)
        Dim nextPoint As Point

        Using g As Drawing.Graphics = Graphics.FromImage(map)
            Dim dPath As New Drawing2D.GraphicsPath
            For i As Integer = 0 To path.Count - 1

                Try
                    nextPoint = path(i + 1)
                Catch
                End Try

                dPath.AddLine(path(i).X * 12 + xMod, _
                              path(i).Y * 13 + yMod, _
                              nextPoint.X * 12 + xMod, _
                              nextPoint.Y * 13 + yMod)
            Next
            l1.CreateGraphics.DrawPath(Drawing.Pens.Black, dPath)
        End Using

---

l1 is a Label. When I call this it draws the path fine, but when I call it again it draws another path but doesn't get rid of the first path.

Basically, I only want one path on the Label at a time.

invalidate l1 before drawing the next path

I have already tried invalidating.
I tried place l1.Invalidate() at the start and end of the method.
I even tried placing it in the calling method.

Using l1.Invalidate() causes the paths to not be drawn at all.

l1.Invalidate() at the start and not at the end of the method should have the right effect

I know nothing about those objects, but I see the AddLine method of dPath being called. That suggests that dPath contains a collection of lines to which you are adding. If that is the case, then there should be a means to clear that collection or else the lines will just be redrawn.

try changing this line:

vb Code:

Dim map As New Bitmap(l1.Size.Width, l1.Size.Height, l1.CreateGraphics)

to this:

vb Code:

Dim map As New Bitmap(l1.Size.Width, l1.Size.Height)

I figured it out. I just put all the code into the Paint event of the label. When I want to draw a line I call l1.Refesh()

@ Shaggy Hiker
dPath does contain multiple lines. The points are stored in path.
Each time I call the method I am creating dPath, so it is empty when I start.

@ .paul.
I did try your second suggestion to no avail.

If there is a way to do this without using the Paint event, I would love to know it. Until then, I am marking this as resolved. Thanks.

in fact, after looking at it again, there is lots of redundant code in your first post.

first you create a bitmap, that you don't use, then a graphics object that you don't use.
i really couldn't suggest what you should try next unless you post the full code, including the values for path() + the values of xMod + yMod, so i can debug it for you.

the problem with drawing on controls is that your drawing is erased next time the control is painted, which is why you should draw in the Paint event