I can't get mobile IP address by my code, Help me please

This my code for get ip address from mobile phone

public TextView text;
text = FindViewById<TextView>(Resource.Id.viewIP);
foreach (IPAddress adress in Dns.GetHostAddresses(Dns.GetHostName()))
{
    text.Text = "IP Adress: " + adress;
}

This code don't have some error but after I ran this code my application it always close. After that I can't open application on my phone.

If somebody can suggest me for change please tell me. Thank for read it.