Hi all,
How can I easily specify that if the parameter is not passed, it should be NULL by default. So in this example $Var1 should always be passed, and I check for that. $Var2 most of the time WILL NOT be passed at all, and it's ok. Instead of doing the following, I need to set $Var2 to default of NULL unless it's passed to the script.

$Var1=$args[0]
$Var2=$args[1]
if (!$args[0]) { write-host "Invalid or missing sql server (Argument 1)" exit }

# If Var2 is not provided it's NULL

if (!$args[1]) {$var -eq $null}

------------
Thanks

I would use param () instead, version that should work on v1 and v2:
param (
$var1 = $(throw 'I really need var1!'),
$var2
)

v2 version:

[CmdletBinding()]
param (
[Parameter(Mandatory = $true, HelpMessage = 'Please provide the script with first argument')]
$var1,
$var2
)

It will force user of the script to pass first argument, and var2 will contain $null if not passed.

HTH
Bartek

Thanks Bartek,
I like the [CmdletBinding()] to make $Var1 mandatory, but since my script is kicked off by scheduling engine, it'll just sit there waiting for $var1 forever, so that's why I need to check for it manually, or exit.


Just curious, how is param () better than $args[0] syntax ? Is that because it's more flexable as a function?

Well, I would expect ValidateNotNullOrEmpty would do the job in such a case, but it kick in only if you run function with empty string or $null. :(
In such a case:
param (
[Parameter()]
[ValidateNotNullOrEmpty()]
$var1 = $(throw "I really need a value for Var1!")

Setting default value in that way was v1 way to make parameter mandatory, but it does not prompt the user for it. ;)

Why param? This way you have more control over parameters being passed to your function. And if user will try to pass more arguments than you expected, it will throw an error too. ;) Of course once you do [CmdletBinding()].
But you can't use CmdletBinding without PARAM().