Continue execution on Exception

Question

Below is the script I want to execute. The issue here is once an exception occurs it stops executing, I used continue in the catch block but that did not work. How do I get it working even after an exception occurs it should loop in foreach.

I also used a while($true) loop but that went into infinite loop. How to go about it?

$ErrorActionPreference = "Stop";
try 
{
# Loop through each of the users in the site
foreach($user in $users)
{
    # Create an array that will be used to split the user name from the domain/membership provider
    $a=@()


    $displayname = $user.DisplayName
    $userlogin = $user.UserLogin


    # Separate the user name from the domain/membership provider
    if($userlogin.Contains('\'))
    {
        $a = $userlogin.split("\")
        $username = $a[1]
    }
    elseif($userlogin.Contains(':'))
    {
        $a = $userlogin.split(":")
        $username = $a[1]
    }

    # Create the new username based on the given input
    $newalias = $newprovider + "\" + $username

    if (-not $convert)
    {
        $answer = Read-Host "Your first user will be changed from $userlogin to $newalias. Would you like to continue processing all users? [Y]es, [N]o"

        switch ($answer)
        {
            "Y" {$convert = $true}
            "y" {$convert = $true}
            default {exit}
        }
    }   

    if(($userlogin -like "$oldprovider*") -and $convert)
    {  

        LogWrite ("Migrating User old : " + $user + " New user : " + $newalias + "    ")
        move-spuser -identity $user -newalias $newalias -ignoresid -Confirm:$false
        LogWrite ("Done")
    }   
} 
}
catch  {
    LogWrite ("Caught the exception")
    LogWrite ($Error[0].Exception)
} 

Answer 1

You use try {...} catch {...} when you want to handle errors. If you want to ignore them, you should set $ErrorActionPreference = "Continue" (or "SilentlyContinue") as @C.B. suggested, or use -ErrorAction "SilentlyContinue" for the particular operation raising the error. If you want to handle errors from a certain instruction, you'd put that instruction in the try {...} catch {...} block, not the entire loop, e.g.:

foreach($user in $users) {
  ...
  try {
    if(($userlogin -like "$oldprovider*") -and $convert) {  
      LogWrite ("Migrating User old : " + $user + " New user : " + $newalias + "    ")
      move-spuser -identity $user -newalias $newalias -ignoresid -Confirm:$false
      LogWrite ("Done")
    }   
  } catch {
    LogWrite ("Caught the exception")
    LogWrite ($Error[0].Exception)
  }
} 

Answer 2

You seem to have placed the "catch" outside the loop body, so that aborts the loop. Put the catch inside the loop

Answer 3

Modified the code as below. Used the following piece of code after move-spuser -identity $user -newalias $newalias -ignoresid -Confirm:$false

if($?)
{
  LogWrite ("Done!")
  LogWrite ("  ")
}
else
{
  LogWrite ($Error[0].ToString())
  LogWrite ("  ")
}

Answer 4

Something that worked for me is to set the $ErrorActionPreference variable to stop, and then reset it back to continue in the catch block:

$e = $ErrorActionPreference
$ErrorActionPreference="stop"

try
{
     #Do Something that throws the exception
}
catch
{
    $ErrorActionPreference=$e

}

$ErrorActionPreference=$e;