PowerShell – Set IP Address

function Set-IPAddress {
		param(	[string]$networkinterface =$(read-host "Enter the name of the NIC (ie Local Area Connection)"),
			[string]$ip = $(read-host "Enter an IP Address (ie 10.10.10.10)"),
			[string]$mask = $(read-host "Enter the subnet mask (ie 255.255.255.0)"),
			[string]$gateway = $(read-host "Enter the current name of the NIC you want to rename"),
			[string]$dns1 = $(read-host "Enter the first DNS Server (ie 10.2.0.28)"),
			[string]$dns2 = $(read-host "Enter the second DNS Server (ie 10.2.0.28)"),
			[string]$registerDns = "TRUE"
		 )
		$dns = $dns1
		if($dns2){$dns ="$dns1,$dns2"}
		$index = (gwmi Win32_NetworkAdapter | where {$_.netconnectionid -eq $networkinterface}).InterfaceIndex
		$NetInterface = Get-WmiObject Win32_NetworkAdapterConfiguration | where {$_.InterfaceIndex -eq $index}
		$NetInterface.EnableStatic($ip, $subnetmask)
		$NetInterface.SetGateways($gateway)
		$NetInterface.SetDNSServerSearchOrder($dns)
		$NetInterface.SetDynamicDNSRegistration($registerDns)		
}

Reference: http://poshcode.org/6000