Does anyone know why this while statement will not return TRUE when I enter "A" or "PTR" into the Read-Host?
$lookupDecision = Read-Host "Do you want results for A or PTR: "
while( $lookupDecision -ne "A" -or $lookupDecision -ne "PTR" ) {
$lookupDecision = Read-Host "Invalid input! Enter A or PTR: "
}
This statement does return TRUE, and will do so no matter what you enter. If you enter A, it results in TRUE because A is not equal to PTR. If you enter PTR it results in TRUE because it's not equal to A. Anything else is not equal to both of them.
The problem here is that you want it eventually return FALSE, so you can move past the while loop to the next section of code. To do this, you need a -and instead of a -or.
$lookupDecision = Read-Host "Do you want results for A or PTR: "
while( $lookupDecision -ne "A" -and $lookupDecision -ne "PTR" ) {
$lookupDecision = Read-Host "Invalid input! Enter A or PTR: "
}
[string]::Compare() is unnecessary here, the default mode of all comparison operators in PowerShell is case-insensitivity when operating on strings. You have to state case-sensitive comparison operations explicitly, ie. "a" -cne "A"
-ine rather than [string]::Compare()Do while's are awesome for prompting users for input
do {
$lookupDecision = Read-Host "Do you want results for A or PTR: "
} while ($lookupDecision -ne "A" -And $lookupDecision -ne "PTR")
-or and won't work. Also, it can confuse users if the prompt never changes. Better to have something to indicate the problem.