private void AddNewOnLine(OnlineListResult newUser)
{
if (!OnLineList.Any(d => d.username == newUser.username))
{
OnLineList.Add(newUser);
}
if (!LoginedStuList.Any(d => d.username == newUser.username))
{
if (newUser.clientRole == ClientRole.Student)
{
LoginedStuList.Add(newUser);
}
}
}