I'd like to access this function in my c# code, is this possible? so in the end the c++ code would call my function and also apply the struct called "sFrameofData".

C++ Code:

//The user supplied function will be called whenever a frame of data arrives.
DLL int Cortex_SetDataHandlerFunc(void (*MyFunction)(sFrameOfData* pFrameOfData));

Would this work perhaps?

C# Code:

[DllImport("Cortex_SDK.dll")]
public extern static int Cortex_SetDataHandlerFunc(ref IntPtr function(ref IntPtr pFrameOfData) );
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