Description: C# preprocessor is fundamentally very similar to C preprocessor and the whole concept in C# has been taken from C language specification. The C preprocessor is a macro processor that is used automatically by the C compiler to transform your program before actual compilation. It is called a macro processor because it allows you to define macros, which are brief abbreviations for longer constructs. But in C# only concept has been taken from C. But the C# compiler does not...