Get the switchport a VM NIC is attached to

gistfile1.txt

$MYHOSTNAME = "Your.Host.Here"
$VMNIC = "vmnic0"

$NS = (((Get-VMhost -name $MYHOSTNAME) | Get-View).ConfigManager.NetworkSystem) 
(((Get-view -ID $NS).NetworkINfo.Pnic |
       Where-Object { $_.Device -eq $VMNIC } | 
       %{ (Get-View -ID $NS).QueryNetworkHint($_.Device) }).ConnectedSwitchPort).PortID