Before we go ahead and talk about how to handle errors or avoid them while writing scripts in PowerShell, let's speak about a few of the inherent features of advanced functions that can help end users. These are Write-Verbose, Write-Error, Write-Warning, and –Whatif. These are not typical error handling ways in PowerShell, but by using these in advanced functions, you can provide more ways to avoid errors in scripts.
Write-Verbose allows you to define more information for end users when they run the script/function/cmdlet with the –Verbose option. The same goes for the Write-Error and Write-Warning options. Defining –Whatif would allow end users to know what exactly the script will do if it is run normally. The following is a sample script showing all of these:
–WhatIf will only show the purpose of the script. If more than two VMnames are provided, then there will be an error message shown but not providing any VM name will result in an error. The following is...
