Windows Batch Files: if else

Question

I\'m doing a simple batch file that requires one argument (you can provide more, but I ignore them).

For testing, this is what I have so far.

if not          


        

Answer 1

Surround your %1 with something.

Eg:

if not "%1" == ""

Another one I've seen fairly often:

if not {%1} == {}

And so on...

The problem, as you can likely guess, is that the %1 is literally replaced with emptiness. It is not 'an empty string' it is actually a blank spot in your source file at that point.

Then after the replacement, the interpreter tries to parse the if statement and gets confused.