From Xojo Documentation
The subnet mask of the user's computer.
The following simple example displays the IP address, Subnet mask, and Mac address for the selected network interface. At start-up, the application detects all the network interfaces installed on the user’s computer and loads them into a PopupMenu. The user then selects the desired network interface and the values are displayed in TextFields.
The PopupMenu's Open event handler is:
For i As Integer = 0 To System.NetworkInterfaceCount - 1
The Change event handler for the PopupMenu is this:
// Get the NetworkInterface object for the selected item
n = System.GetNetworkInterface(Me.SelectedRowIndex)
// Get the MAC Address
MacAddressField.Value = n.MACAddress
// Get the IP Address
IPAddressField.Value = n.IPAddress
// Get the Subnet Mask
SubnetMaskField.Value = n.SubnetMask