Check if unmanaged DLL is 32-bit or 64-bit?

Question

How can I programmatically tell in C# if an unmanaged DLL file is x86 or x64?

Answer 1

Even easier: check out the System.Reflection.Module class. It includes the GetPEKind method, which returns 2 enums that describe the type of code and the CPU target. No more hex!

(the rest of this very informative post was copied shamelessly from http://www.developersdex.com/vb/message.asp?p=2924&r=6413567)

Sample code:

Assembly assembly = Assembly.ReflectionOnlyLoadFrom(@"");
PortableExecutableKinds kinds;
ImageFileMachine imgFileMachine;
assembly.ManifestModule.GetPEKind(out kinds, out imgFileMachine);

PortableExecutableKinds can be used to check what kind of the assembly. It has 5 values:

ILOnly: The executable contains only Microsoft intermediate language (MSIL), and is therefore neutral with respect to 32-bit or 64-bit platforms.

NotAPortableExecutableImage: The file is not in portable executable (PE) file format.

PE32Plus: The executable requires a 64-bit platform.

Required32Bit: The executable can be run on a 32-bit platform, or in the 32-bit Windows on Windows (WOW) environment on a 64-bit platform.

Unmanaged32Bit: The executable contains pure unmanaged code.

Following are the links:

Module.GetPEKind Method: http://msdn.microsoft.com/en-us/library/system.reflection.module.getpekind.aspx

PortableExecutableKinds Enumeration: http://msdn.microsoft.com/en-us/library/system.reflection.portableexecutablekinds(VS.80).aspx

ImageFileMachine Enumeration: http://msdn.microsoft.com/en-us/library/system.reflection.imagefilemachine.aspx