If a function parameter should receive a string of a given length only, you should use the following validation attribute. In the example, it limits filenames to eight characters:
function Get-FileName {
param(
[ValidateLength(1,8)]
[String]
$FileName
)
param(
[ValidateLength(1,8)]
[String]
$FileName
)
"Your filename {0} is {1} chars long" -f $FileName, $FileName.Length
}
