managed, unmanaged

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Enable function-level control for compiling functions as managed or unmanaged.

  
      #pragma managed  
#pragma unmanaged  
#pragma managed([push,] on | off)  
#pragma managed(pop)  

The /clr compiler option provides module-level control for compiling functions either as managed or unmanaged.

An unmanaged function will be compiled for the native platform, and execution of that portion of the program will be passed to the native platform by the common language runtime.

Functions are compiled as managed by default when /clr is used.

When applying these pragmas:

• Add the pragma preceding a function but not within a function body.

• Add the pragma after #include statements. Do not use these pragmas before #include statements.

The compiler ignores the managed and unmanaged pragmas if /clr is not used in the compilation.

When a template function is instantiated, the pragma state at the time of definition for the template determines if it is managed or unmanaged.

For more information, see Initialization of Mixed Assemblies.

// pragma_directives_managed_unmanaged.cpp  
// compile with: /clr  
#include <stdio.h>  
  
// func1 is managed  
void func1() {  
   System::Console::WriteLine("In managed function.");  
}  
  
// #pragma unmanaged  
// push managed state on to stack and set unmanaged state  
#pragma managed(push, off)  
  
// func2 is unmanaged  
void func2() {  
   printf("In unmanaged function.\n");  
}  
  
// #pragma managed  
#pragma managed(pop)  
  
// main is managed  
int main() {  
   func1();  
   func2();  
}  

In managed function.  
In unmanaged function.  

Pragma Directives and the __Pragma Keyword