VB .NET reverse engineering preprocessing

Chapter 16 Working with VB .NET

VB .NET reverse engineering preprocessing

VB .NET files may contain conditional code that needs to be handled by preprocessing directives during reverse engineering. A preprocessing directive is a command placed within the source code that directs the compiler to do a certain thing before the rest of the source code is parsed and compiled. The preprocessing directive has the following structure:

#directive symbol

Where # is followed by the name of the directive, and symbol is a conditional compiler constant used to select particular sections of code and exclude other sections.

In VB .NET symbols have values.

In the following example, the #if directive is used with symbols FrenchVersion and GermanVersion to output French or German language versions of the same application from the same source code:

      #if FrenchVersion Then
       '  <code specific to French language version>.
      #ElseIf GermanVersion Then
        ' <code specific to French language version>.
      #Else
        ' <code specific to other language version>.
      #End If

You can declare a list of symbols for preprocessing directives. These symbols are parsed by preprocessing directives: if the directive condition is true the statement is kept, otherwise the statement is removed.