Catching errors

Capturing an error so that a script can react to that error depends on the error type.

• Non-terminating errors can be captured by using ErrorVariable
• Terminating errors can be captured using either a try, catch, and finally statement, or by using a trap statement

The -ErrorVariable parameter can be used to create a scoped alternative to the $Error variable.

ErrorVariable

The $Error variable is a collection (ArrayList) of handled and unhandled errors raised in the PowerShell session.

You can use the -ErrorVariable parameter to name a variable that should be used for a specific script. The ErrorVariable accepts the name of a variable and is created as an ArrayList.

The following function writes a single error using the Write-Error command:

function Invoke-Something { 
    [CmdletBinding()] 
    param ( ) 
 
    Write-Error 'Invoke-Something Failed' 
}

The command can be run using the -ErrorVariable parameter...