Import unmanaged dlls at runtime

DLLs are never imported. Importing a DLL is a misleading concept. Type libraries are imported. If you think in terms of importing type libraries, you will understand better.

Is the DLL a COM object or ActiveX control? Is there a type library for it? If the answer to all of that is no, then you probably cannot import type information. I am not sure, but I think it is possible to create a type library for a DLL that does not have one, but I don't know the details. You could write a C++ program that is a COM object that calls the DLL, and then that COM object could be imported. Or you could write a C# class library that uses the DLL as an unmanaged DLL, and then the class library could be used by other programs.

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Sam Hobbs16y ago
DLLs are never imported. Importing a DLL is a misleading concept. Type libraries are imported. If you think in terms of importing type libraries, you will understand better.

Is the DLL a COM object or ActiveX control? Is there a type library for it? If the answer to all of that is no, then you probably cannot import type information. I am not sure, but I think it is possible to create a type library for a DLL that does not have one, but I don't know the details. You could write a C++ program that is a COM object that calls the DLL, and then that COM object could be imported. Or you could write a C# class library that uses the DLL as an unmanaged DLL, and then the class library could be used by other programs.