How can i build a class library so that it outputs two different DLL's for two different frameworks, ignoring some methods/classes in each build?

Question

Say I have a class library that contains both .net2.0 compatible code, and .net5 compatible code. I want to be able to build the project for both frameworks, where the .net5 code is ignored when building the .net2.0 build. This way I can maintain only one version whilst catering for both frameworks.

Answer 1

Check the #define together with #if... it set precompiler test and that's how you may achieve that... there may be other simpler options, but this one works mostly like in C++

This is an example from the link:

#define DEBUG  
//#define TRACE  
#undef TRACE  

using System;  

public class TestDefine  
{  
  static void Main()  
   {  
     #if (DEBUG)  
       Console.WriteLine("Debugging is enabled.");  
     #endif  

     #if (TRACE)  
       Console.WriteLine("Tracing is enabled.");  
     #endif  
   }  
 }  
// Output:  
// Debugging is enabled.  

so the idea will be to create #define NET5 and #define NET2 and test in the code for the defined one depending in what you are compiling for. that way the compiler will ignore one or the other...

 #define NET5
 #define NET2

 #if (NET5)  
       NET5 code...
 #endif

 #if (NET2)  
       NET2 code...
 #endif