Would this work better with loops rather than functions? - powershell

Question

The following code works, but I'm interested in knowing if there would have been a more efficient way of writing the script, may be by using loops, or it this is the correct way to write such a script? The problem I had when trying to use loop statements was that I couldn't work out how to put the $Dialog "OK" into a loop where it can then loop back to itself if the IP Address still wasn't valid.
The idea of the script is to get the (first three octets of an) IP address, and see if it's valid (i.e not 0.0.0.0 or 169.254.*) before storing it as a variable, and if it isn't valid to throw a dialog box to give to administrator the opportunity to correct it, and then check again, and so on.
function Check-IP
{
$IPSiteAddress = Get-IPAddress
if ($IPSiteAddress -like "0.*" -or $IPSiteAddress -like "169.254.*") {DialogBox-IP}
}
function Get-IPAddress
{
(Get-WmiObject Win32_NetworkAdapterConfiguration |
Where { $_.IPAddress } |
Select -Expand IPAddress).split('.')[0..2] -join '.'
}
function DialogBox-IP
{
$IPDialog = [System.Windows.Forms.MessageBox]::show( "This computer doesn't have a valid IP Address.
Please correct the IP Address and click OK, or click Cancel to exit.","No Network Connection",1)
if ($IPDialog -eq "OK") {Check-IP} else {exit}
}
Check-IP
$IPSiteAddress = Get-IPAddress
If anyone has a nicer solution or, any thoughts, I'll love to hear them

Answer 1

function Check-IP
{
param ($IPSiteAddress)
return !($IPSiteAddress -like "0.*" -or $IPSiteAddress -like "169.254.*")
}
function Get-IPAddress
{
(Get-WmiObject Win32_NetworkAdapterConfiguration | Where { $_.IPAddress } | Select -Expand IPAddress).split('.')[0..2] -join '.'
}
while (!(Check-IP Get-IPAddress))
{
DialogBox-IP
}