Simple ways to disable parts of code

Question

This isn\'t a typical question to solve a specific problem, it\'s rather a brain exercise, but I wonder if anyone has a solution.

In development we often need to disable

Answer 1

the following logic should contain the simplest approach

if(isMode1)
{
    //Code for mode1
}
else
{
    //Code for other modes
}

although I think the correct way is to use PreProcessor Directives