Home/ Questions/Q 541851
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-13T10:23:08+00:00

I have an application which uses C# front end and a C++ DLL as

  • 0

I have an application which uses C# front end and a C++ DLL as the backend. I am trying to pass an array from C# code to the C++ code in the DLL which changes the values in that array. But when I try to retrieve the values of the array from C# code after the call is made to the C++ DLL function, the changes are not being reflected. I want the changes to be reflected. Please help me in this regard.

Thanks,
Rakesh.

The following are the signatures of the functions that I am using.

In C#:

testStruct(structs, len);

structs is the array of structures that I am passing.

In C++:

extern "C"  __declspec(dllexport)  void __cdecl  testStruct(structure1*  arrStruct, int len)

arrStruct is the array of structures which receives the ones passed from C#.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    The array is being marshalled by value to the C++ DLL, which means your C++ DLL is working on a copy of the original array. The array needs to be marshalled by reference in order for your C++ code to manipulate the same array which your C# code is referring to.

    Rather than investigating methods of marhsalling the array by reference you may want to consider changing your C++ interface so that the manipulated array is returned to your C# code as, for example, a return value.

    • 0