Powershell get computer name and add to AD group - powershell

Question

I am trying to utilize Powershell to get the computer name it’s currently running on and then add that computer to a security group and I’m stuck.
Forcing myself to learn Powershell better and got this from a co-worker but not sure how to edit it for my needs. This script will be used to run after a certain package has been installed to grant access. Here is what I have so far:
param(
[string[]]$mname,
[string[]]$gname
)
foreach($m in $mname.split(','))
{
$mobj = get-adcomputer $m
foreach($g in $gname.split(','))
{
Add-ADGroupMember "GROUP_NAME" -Members $mobj
}
}
ERROR:
You cannot call a method on a null-valued expression.
At C:\Scripts\Add-MachineToCollectionGroup.ps1:6 char:15
+ foreach($m in $mname.split(','))

Answer 1

Just add your groupname at the top, also if you aren't running Powershell 5 you may need to change Add-ADGroupMember $groupobj -Members $computerobj to be Add-ADGroupMember $groupobj -Member $computerobj I think they changed that.
Also add -whatif to the end of the last line to test it (It'll tell you what it would have done without the whatif).
Oh also you will need to run this from an account that has AD access to add the machine to the group and the computer must have the activedirectory module installed.
$Groupname = "ENTER GROUP NAME HERE"
$computerobj = Get-ADComputer $env:COMPUTERNAME
$groupobj = Get-ADGroup $Groupname
Add-ADGroupMember $groupobj -Members $computerobj -WhatIf