No, they aren't. They are like comments. Look at Pre-processing directives
The pre-processing directives provide the ability to conditionally
skip sections of source files, to report error and warning conditions,
and to delineate distinct regions of source code. The term
"pre-processing directives" is used only for consistency with the C
and C++ programming languages. In C#, there is no separate
pre-processing step; pre-processing directives are processed as part
of the lexical analysis phase.
Pre-processing directives are not tokens and are not part of the
syntactic grammar of C#. However, pre-processing directives can be
used to include or exclude sequences of tokens and can in that way
affect the meaning of a C# program.