Windows PowerShell 3.0 Step by Step - Cdn.oreilly.com - O'Reilly

FIGURE 1-1 Errors appear when attempting to update help files that do not support updatable help.
One way to update help and not to receive a screen full of error messages is to run the
Update-Help cmdlet and suppress the errors all together. This technique appears here:
Update-Help -Module * -Force -ea 0
The problem with this approach is that you can never be certain that you have actually received
updated help for everything you wanted to update. A better approach is to hide the errors during the
update process, but also to display errors after the update completes. The advantage to this approach
is the ability to display cleaner errors. The UpdateHelpTrackErrors.ps1 script illustrates this technique.
The first thing the UpdateHelpTrackErrors.ps1 script does is to empty the error stack by calling the
clear method. Next, it calls the Update-Help module with both the module parameter and the force
switched parameter. In addition, it uses the ErrorAction parameter (ea is an alias for this parameter)
with a value of 0. A 0 value means that errors will not be displayed when the command runs. The
script concludes by using a For loop to walk through the errors and displays the error exceptions. The
complete UpdateHelpTrackErrors.ps1 script appears here.
note For information about writing Windows PowerShell scripts and about using the For
loop, see Chapter 5.
UpdateHelpTrackErrors.ps1
$error.Clear()
Update-Help -Module * -Force -ea 0
For ($i = 0 ; $i -le $error.Count ; $i ++)
{ "`nerror $i" ; $error[$i].exception }
14 Windows PowerShell 3 Step by Step