需要做一个能转发在线用户列表的聊天服务器 以下各句代码的具体作用是什么呢？2001表示登陆成功。还望各位给我指点下，能否在重点代码上加个注释？？
foreach (ClientService item in clietn)
{
if (item.mysock.GetHashCode() == model.TcpClientHashCode)
{
item.SendMessage(loginState);
if (loginState == "2001")
{
foreach (OnlineModel onLineItem in onlineList)
{
if (onLineItem.TcpClientHashCode != model.TcpClientHashCode)
{
string userId = onLineItem.UserId.ToString();
while (true)
{