I am trying to draw a rectangle for every record in a dataset.
The drawing function will occur within a For Each loop and each record has a
different XY position, so the idea is that the final result will have a
single image with multiple rectangles. I have tried using bitmap methodology
of doing this, but that doesn't get multiple objects on the image - only the
final item is saved and displayed.

Is there a way that I can draw the rectangle directly to the client, and
then next iteration through the loop, draw a different rectangle in a new
location without losing the last image?

Thanks,

I'm assuming that your drawing to the screen and your stuff is disappearing
between draw cycles.

Are you respecting the laws of GetGraphics? (See the GDI+ FAQ)

Perhaps you should draw your rectangles to an image in memory and then
display that instead.

--
--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

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"NathanC" <NathanC (AT) discussions (DOT) microsoft.com> wrote

I'll look into that - here is my code:

Dim i As Int32
For i = 0 To dvGetSeatsByScreen.Count - 1

dvGetSeatStatus.RowFilter = "id='" &
dsGetSeatsByScreen.Tables("Table").Rows(i).Item("s eat_status").ToString() &
"'"
fore_color = dvGetSeatStatus(0)("fore_color").ToString()
back_color = dvGetSeatStatus(0)("back_color").ToString()
status_legend = dvGetSeatStatus(0)("status_legend").ToString()

fore_color = Drawing.Color.FromArgb(fore_color)
back_color = Drawing.Color.FromArgb(back_color)

xpos =
Convert.ToInt32(dsGetSeatsByScreen.Tables("Table") .Rows(i).Item("xpos").ToString())
ypos =
Convert.ToInt32(dsGetSeatsByScreen.Tables("Table") .Rows(i).Item("xpos").ToString())

seat.DrawRectangle(Drawing.Pens.Black, xpos, ypos, 5, 10)
seat.FillRectangle(Drawing.Brushes.Crimson, xpos, ypos, 5, 10)

Next

Response.ContentType = "image/gif"
bitmap.Save("C:\Inetpub\wwwroot\Tessitura\images\" &
ViewSelection.SelectedItem.Text & ".gif", Drawing.Imaging.ImageFormat.Gif)

"Bob Powell [MVP]" wrote:

I'm an idiot - I was calling seat.Clear earlier in the code - that fixed it.
What a dummy.

Thanks,

"NathanC" wrote: