I have a DLL written in C in source code. This is the code for the General Polygon Clipper (in case you are interested). I'm using it in a C# project via the C# wrapper provided on the homepage. This comes with a precompiled DLL.
Since switching to a 64bit Development machine with Visual Studio 2010 and Windows 7 64 bit, the application won't run anymore. This is the error I get:
An attempt was made to load a program with an incorrect format.
This is because of DLLImporting the 32bit gpc.dll, as I have gathered from stuff found on the web.
I assume this will all go away if I recompile the DLL to 64bit, but can't for the love of me figure out how to do so. My C skills are basic, in that I can write a C program with the GNU tools, but have no experience with various compilers / processors / IDEs etc.
I believe I could port this to C#. By that I mean I trust myself to actually pull it off. But I'd prefer not to, since it is a lot of work that I'd prefer a compiler to do for me ;)
It could be as easy as creating a new platform:
- open property pages of project (ALT+ENTER)
- choose platform x64 in dropdown menu in top-right corner
- if the platform does not already exist, create a new one
- rebuild
- make sure you are checking the right artefacts when built, as you now probably have a different output directory.
来源：https://stackoverflow.com/questions/3060452/how-to-compile-a-c-dll-for-64-bit-with-visual-studio-2010