Can someone tell me, why this function call does not work and why the argument is always empty ?
function check([string]$input){
Write-Host $input #empty line
$count = $input.Length #always 0
$test = ([ADSI]::Exists('WinNT://./'+$input)) #exception (empty string)
return $test
}
check 'test'
Trying to get the info if an user or usergroup exists..
Best regards
$input is an automatic variable.
https://technet.microsoft.com/ru-ru/library/hh847768.aspx
$InputContains an enumerator that enumerates all input that is passed to a function. The
$inputvariable is available only to functions and script blocks (which are unnamed functions). In the Process block of a function, the$inputvariable enumerates the object that is currently in the pipeline. When the Process block completes, there are no objects left in the pipeline, so the$inputvariable enumerates an empty collection. If the function does not have a Process block, then in the End block, the$inputvariable enumerates the collection of all input to the function.
Perhaps use a param block for parameters.
Update: the problem seems to be fixed if you don't use $input as a parameter name, maybe not a bad thing to have proper variable names ;)
Also Powershell doesn't have return keyword, you just push the object as a statement by itself, this will be returned by function:
function Get-ADObjectExists
{
param(
[Parameter(Mandatory=$true, ValueFromPipeline=$true)]
[string]
$ObjectName
)
#return result by just calling the object (no return statement in powershell)
([ADSI]::Exists('WinNT://./'+$ObjectName))
}
Get-ADObjectExists -ObjectName'test'
$input is a system var you shouldn't use, updated sample
return keyword and in some scenarios its quite convenient to use it: technet.microsoft.com/en-us/library/…
param block, return keyword and even took me a while to figure out $input was an automatic variable... pretty bad... at least I learned from this too!