We are working on a product which requires a similar functionality of having the thumbnail generated for all the pdf files selected.
After reading and researching a lot I am totally confused as our solution is hosted on godaddy and not sure if we could use your solution? We don’t have control over the box. Will your solution still fit my needs?

Secondly for most of the solution that I read they had a pre-requisite of having the Adobe Acrobat to be installed (not reader) but fully licensed version? Is it required in this case?

You can use this code:
public static byte[] StringToAnsi(string original)
{
return System.Text.Encoding.ASCII.GetBytes(original + “”);
}

Thanks again

thanks for this great library. I have a problem getting this work on a webapplication. when i debug my webapplication (”F5″ in Visual Studio 2008) it works great. But when i access the webapplication outside of vs2008 (http://localhost/…) the JPG doesn’t get generated. There is also no exception thrown.

The GS Bin is set in the PATH variable. The gsdll32.dll is in my system32-folder.

Maybe the security settings of the IIS-Server are wrong?

greetings
Klaus

there is a lille error in your Wrapper.
The first argument of the arguments you supply in
the method InitAPI(gsInstancePtr, args.Length, args)
is allways ignored by the dll.

So your arguments should start with

return new[]
{
“”,
“-q”,
“-dQUIET”,
….

maybe you didn’t recognize this behavior because -q and -dQuit do the same.

Tobias

You don’t need to add DLL to references. This is not .NET but native PE file (Windows DLL).

Ghostscript should be installed with all it’s libraries, and PATH variable should contain gs bin folder (”C:\Program Files\gs\gs8.70\bin” or other directory where you have gs installed )

I’ve tried to use your code in Windows 7 and Windows XP with visualstudio 2008.When I try to add refrenece for gsdll32.dll to a Windows Forms project I got an error saying it is not a valid com component (gsdll32.dll)

Any idea how to overcome from this error and able to run the program?

Thanks

Thanks for posting this. I honestly had never run across your project before, but I’m glad there’s a project out there that appears to be further along than I am.

http://code.google.com/p/gouda/

I started in on some work to implement the drawing surface callbacks. Right now, the text based callbacks for output/errors works, but I haven’t successfully built a fully functional graphics surface for Ghostscript to render to. Haven’t had much time to work on it lately, so not much has changed in the past year.

If you, or anyone else would like to help out with that project, we could probably get more work done as a team, rather than having multiple projects.

Also, for those of you who are interested in leveraging all the wonderful open source PostScript tools out there in your .Net code, there’s another project that I started called Parrano which is a wrapper to PsLib ( http://code.google.com/p/parrano/ ).

Thanks,
Troy

You may want to look at a PDF generation library like iTextSharp.

Once thumbnails are created, is there anyway to embed them as thumbnails in the PDFs, so that it displays on the left side in the Adobe Reader? Though recent versions of Adobe Reader creates thumbnails dynamically, old versions dont. Thats why.

Thanks
Srikanth

can you help me detect the colored pages in a pdf files using this wrapper?

thanks

[DllImport("gsdll32.dll", EntryPoint = "gsapi_new_instance")]
private static extern int CreateAPIInstance(out IntPtr pinstance,
IntPtr caller_handle);

[DllImport("gsdll32.dll", EntryPoint = "gsapi_init_with_args")]
private static extern int InitAPI(IntPtr instance, int argc, string[] argv);

[DllImport("gsdll32.dll", EntryPoint = "gsapi_exit")]
private static extern int ExitAPI(IntPtr instance);

[DllImport("gsdll32.dll", EntryPoint = "gsapi_delete_instance")]
private static extern void DeleteAPIInstance(IntPtr instance);

This would remove the need for some of your more complicated code (including StringToAnsi).

Thanks for all your hard work!

A couple of notes on changes I made to get it working:
- I needed to put gsdll32.dll in my system32, or alternatively, load it with LoadLibrary.
- I needed to change the line return new[] to actually declare a temp string[] and return it explicitly at the bottom of the function.
- I added a call to Cleanup() at the bottom of your CallAPI(), because you must have called it somewhere outside of your code snippets.
- I replaced your instances of “var” to appropriate type names. “var” must have represented something specific in your system that’s not native to .NET I guess.

Thanks again for showing us how to implement something that should be truly simple but is, in fact, disgustingly difficult and frustrating!