Powershell function failure - powershell

Question

I swear I'm missing something easy here...
Here's a simple script to get disk info:
function get-disks {
try { $disks = gwmi win32_logicaldisk -co $server}
catch { write "$server : Can't connect"}
}
get-disks
$disk.deviceid
The gwmi command alone works perfectly. The "$disks = gwmi..." command alone works perfectly. The try {...}catch{...} lines run alone work perfectly.
But as soon as I load the function and call 'get-disks' I receive no errors, but $disks is empty.

Answer 1

The $server parameter, and the $disks variable are local to the inside function and not visible (not defined) outside of the function.
You need to provide the server name as a function parameter (from the outside in), and you need to return the $disks variable value from the function (from the inside out) and capture it's value.
function Get-Disks {
param(
[Parameter(Mandatory = $true)]
[string] $Server
)
try {
$result = gwmi win32_logicaldisk -co $Server;
return $result # <--
}
catch { write "$Server : Can't connect"}
}
$disks = Get-Disks -Server "localhost"
Note that the $result variable inside the function is another
variable the the $disks variable outside of the function.
For simplicity, you can write the function as follows:
function Get-Disks {
param(
[Parameter(Mandatory = $true)]
[string] $Server
)
# just return the output of gwmi directly
gwmi win32_logicaldisk -co $Server;
}