Error trap on extraneous script parameters

Question

I have a script that accepts named parameters at the command line, and I would like to error trap any extraneous parameters, rather than having a malformed shortcut cause an error. I tried just wrapping the Param section at the top of the script in a Try/Catch
but that doesn't work at all. Is there any mechanism to address this more gracefully, or do i just need to document proper argument syntax and let users see the error if they mess it up?
Note, I used Try/Catch with and without cmdletbinding, and with camdletbinding in and out of the Try. Some variations caused errors, and some caused all parameters to be ignored, even the ones that where correctly being passed.
Gordon

Answer 1

So, basically what I want to do is have two named parameters, one required and one optional, and then catch the error when someone includes a third, or gets a name wrong. It seems like there is no way to catch that, you are just going to get a standard
PowerShell error. Not the end of the world, but like not being able to natively run a powershell script with no console at all, a little annoying, if in fact it can't be done.
It sounds like this is what you want (as far as the 1 mandatory and 1 option params go):
Function Test {
[cmdletbinding()]
Param (
[parameter(Mandatory=$True)]
[string]$Param1,
[parameter()]
[string]$Param1
#CODE HERE
Unfortunately, you will not be able to get around the issue of someone attempting to use a 3rd parameter and having an error thrown. This will happen at runtime and can't be caught.
Boe Prox
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