Checking exit code of last command using “if” statement

You’re talking about “exit code”. If you mean $LastExitCode automatic variable, it is only populated when you call windows program, RAR for example:

$x=rar
$LastExitCode

It will return exit code 7 (if you have RAR installed).

cmdlets, however, don’t fill this variable. You can use another automatic variable $? for this:

$x=gci
$?

It only gives $True if command completed successfully or $False if there was an error.