Unable to get value from function in Powershell - powershell

Question

I am trying to get the value from the function which contains 2 values, one is pointed from the current method, and another value is null.
What I expect is to print out the $convertAccountEx value from the function, but it gives me nothing. I have tried to give $null value for $convertAccountEx, but nothing changes.
function ConvertTo-Date(){
Param ($accountEx,$convertAccountEx)
if($accountEx.accountExpires -eq 0){
$convertAccountEx = "Never"
}
else{
$convertAccountEx = [DateTime]::FromFileTime($AccountEx.accountExpires)
}
}
$userObjects = $ADSearch.FindAll()
foreach ($user in $userObjects){
$accountEx = $user.Properties.Item("accountExpires")
ConvertTo-Date -accountEx $accountEx.accountExpires -convertAccountEx $convertAccountEx
$convertAccountEx
}

Answer 1

Your code should look like this:
function ConvertTo-Date(){
Param ($accountEx)
if($accountEx.accountExpires -eq 0){
$convertAccountEx = "Never"
}
else{
$convertAccountEx = [DateTime]::FromFileTime($AccountEx.accountExpires)
}
$convertAccountEx
}
$userObjects = $ADSearch.FindAll()
foreach ($user in $userObjects){
$accountEx = $user.Properties.Item("accountExpires")
ConvertTo-Date -accountEx $accountEx.accountExpires
}
The issue you ran into is called scoping. The idea is, that every variable you create, should be exclusive to its running scope. So the var inside your function is - by definition - a different var than outside, even if they share the name. An easy way to go around this in your example is, to just return the value from you function (by calling it).
What I would advise is: Don't just return the value, but append it to the objects you create. Here a (really) simple example:
function Add-Info {
Param( $user )
$user | Add-Member -NotePropertyName NewProperty -NotePropertyValue 'SomeValue'
$user
}