Question

I need to use a DLL coded in C++ in a C# application, there is a method in the DLL with receives a object declared in the C++ and I don’t know how to parse a equivalent object maded in C# to the function of the DLL

Can someone help me?

Answer 1

You will need to use the System.Runtime.InteropServices namespace with Platform Invoke if the c++ code is not managed or COM. You will need to define the structure in your C# application and pass an object of whatever type your structure is to the method you are using Platform Invoke on. To tell you anymore, I need to see some header files.

Here is a sample :

c++ header:

struct MyStruct
{
   int size;
   char* data;
}

bool MethodToInvoke(MyStruct* obj);

c# declarations:

struct MyStruct
{
  int size;
  string data; 
}

[DllImport("YourDllHere.dll")]
static extern bool MethodToInvoke(ref MyStruct obj);

Of course, it could get much more complicated but that is the general idea.

It can and may get really nasty when you have to worry about calling conventions and marshaling arrays. Regardless the world needs to see some code from you.