private void Submit_Click(object sender, RoutedEventArgs e)
{
 user temp = new user();
 temp.Username = UserName.Text;
 temp.Password = Password.Text;
 dataBase.AddTouser(temp);
 IAsyncResult result = dataBase.BeginSaveChanges(new AsyncCallback (OnSaveChangesCompleted), temp);
}

void OnSaveChangesCompleted(IAsyncResult result)
{
 try
 {
    string name = ((user) result.AsyncState).Username.ToString();
    dataBase.EndSaveChanges(result);
 }
 catch (DataServiceRequestException ex)
 {
     MessageBox.Show("OnSaveChangesCompleted Error: " + ex.ToString());
 }
}

public static void InitializeService(IDataServiceConfiguration config)
{
 config.SetEntitySetAccessRule("*", EntitySetRights.All);
 config.SetServiceOperationAccessRule("*", ServiceOperationRights.All);
}