SYSK 157: Conditional Methods

One of the less known features in .NET is conditional methods, which allow developers to create methods whose calls are included or excluded during compilations based on a preprocessing symbol.

 

Say, you want to execute a certain method only under certain conditions known at compilation time.  In the “old days”, you’d use #if…#endif pre-processor definitions.  In .NET, you can use the System.Diagnostic.ConditionalAttribute class to do the same:

 

private void Method1()

{

                        . . .

            Method2();

. . .

}

// NOTE: Make sure to define MYCONDITION conditional compilation symbol in

// project properties -> build tab

[System.Diagnostics.Conditional(“MYCONDITION”)]

private void Method2()

{

. . .

}

In effect, of MYCONDITION is not defined, Method2 call is a no-op.  Most commonly used condition is DEBUG…

 

BEWARE: One would wish that the following would be allowed:

[System.Diagnostics.Conditional(“DEBUG”)]

private void Method2()

{

// TODO: add debug version specific code

}

 

[System.Diagnostics.Conditional(“RELEASE”)]

private void Method2()

{

// TODO: add release version code

}

 

But, it will not compile.  It’s unfortunate, especially since the following compiles without any problems:

#if DEBUG

private void Method2()

{

// TODO: add debug version code

}

            #else

private void Method2()

{

// TODO: add release version code

}

#endif

 

Well, may be in .NET 3.0?