Find out whether an environment variable contains a substring

Question

I need to find out if a certain environment variable (let\'s say Foo) contains a substring (let\'s say BAR) in a windows batch file. Is there any way to do this using only

Answer 1

@mythofechelon: The %var:str=% part removes str from var. So if var contains str on the left side of the equation, it will be removed on the right side - thus the equation will result in "false" if str was found in var or "true" if str was not present in var.