Dynamically generated png images

[Chris Jones]

I am creating a web page that dynamically generates an
image, which is placed in an Image control. Everything
works fine for .gif and .jpeg files. I would prefer
using .png format, but that doesn't seem to work.

Here's how it's setup.

The Image control has URL property "image.aspx ".

The Page_Load method of image.aspx contains the code

{
//generate image
Bitmap bitmap = ...
//Return the image
Response.Conten tType = "image/png";
bitmap.Save(Res ponse.OutputStr eam,ImageFormat .Png);
}

If ContentType is "image/jpeg" and bitmap.Save's 2nd
parameter is ImageFormat.Jpe g, everything works fine.
Same for ContentType = "image/gif" and bitmap.Save's 2nd
argument is ImageFormat.Gif . When the code appears as
above, the Image control displays the dreaded "X" icon
indicating that the image can't be found.

Note that I can use a different version of the Save
method for the bitmap to write the .png image to a file.
I can then open the file successfully in IE.

I am using VS.NET 2002 and .NET framework 1.0.

Thanks for your help.

Chris Jones
LogexSoft
cvjones17@yahoo .com

[Kevin Spencer]

Re: Dynamically generated png images

Unless the browser you're working with supports PNG files, this is pretty
much what you should expect.

HTH,

Kevin Spencer
Microsoft FrontPage MVP
Internet Developer

http://www.takempis.com

Big things are made up of
lots of Little things.

"Chris Jones" <cvjones17@yaho o.com> wrote in message
news:0a7101c33c ae$1a0bc1a0$a50 1280a@phx.gbl.. .[color=blue]
> I am creating a web page that dynamically generates an
> image, which is placed in an Image control. Everything
> works fine for .gif and .jpeg files. I would prefer
> using .png format, but that doesn't seem to work.
>
> Here's how it's setup.
>
> The Image control has URL property "image.aspx ".
>
> The Page_Load method of image.aspx contains the code
>
> {
> //generate image
> Bitmap bitmap = ...
> //Return the image
> Response.Conten tType = "image/png";
> bitmap.Save(Res ponse.OutputStr eam,ImageFormat .Png);
> }
>
> If ContentType is "image/jpeg" and bitmap.Save's 2nd
> parameter is ImageFormat.Jpe g, everything works fine.
> Same for ContentType = "image/gif" and bitmap.Save's 2nd
> argument is ImageFormat.Gif . When the code appears as
> above, the Image control displays the dreaded "X" icon
> indicating that the image can't be found.
>
> Note that I can use a different version of the Save
> method for the bitmap to write the .png image to a file.
> I can then open the file successfully in IE.
>
> I am using VS.NET 2002 and .NET framework 1.0.
>
> Thanks for your help.
>
> Chris Jones
> LogexSoft
> cvjones17@yahoo .com
>[/color]