public AddPersonViewModel(String n, String p, View.AddPersonWindow o)
 {
     Lastname  = n;
     Firstname = p;
     AddressP  = "";
     Zip       = "";
     City      = "";
     Phone     = "";
     Mail      = "";
     win       = o;
 }
 private void add()
 {
     View.AddPersonWindow win = new View.AddPersonWindow(Name, Firstname);
     win.Show();
 }