基于.NET的多用户客户端设计

void CCommunicationDlg::OnBnClickedQuery()//"发送"按钮的响应函数
{ lSocket=NULL;
UpdateData();
id=atoi(m_strQueryId); //获得用户输入的连接号
POSITION pos;
if(!s_info.IsEmpty())
{ socket_info info=s_info.GetHead();
if(id>=s_info.GetCount()) //可选择的id必须小于链表的大小
MessageBox("the data is larger than the count of the list","Alert",MB_OK);
else{ for(pos=s_info.GetHeadPosition();;) //遍历整个链表
{ if(info.id==id&&!info.s_client==NULL)
{ lSocket=info.s_client; //将用户指定的连接的socket赋予lSocket lSocket->Send(m_strSendData,m_strSendData.GetLength());
//发送m_strSendData文本框中的文本
break; }
if(pos==NULL) break;
else info =s_info.GetNext(pos);
}
}
}else AfxMessageBox("the queer is empty!"); //链表为空
}

void CCommunicationDlg::OnBnClickedAdd() //"接收"按钮的响应函数
{ UpdateData();
BOOL MsgEnd=TRUE;
int iRecv; //每次读取的字符数
if(!lSocket==NULL)
{ memset(pBuf,0,100); //清空缓冲区
do{ iRecv=lSocket->Receive(pBuf,100);//接收数据
if(iRecv<100&&iRecv>0) { MsgEnd=TRUE;}
pBuf[iRecv]=0; //给缓冲区结尾，即赋'\0'
}while(!MsgEnd);
m_ReceData.SetSel(0,-1);
m_ReceData.ReplaceSel(pBuf); //在m_ReceData文本框中显示接收的字符
} else AfxMessageBox("the socket was disconnected");
}

void CCommunicationDlg::OnBnClickedCancel()//"断开该连接"按钮的响应函数

……
socket_info info=s_info.GetAt(s_info.FindIndex(id)); //找到id对应的结构体
if(!info.s_client==NULL){
if(info.s_client->ShutDown(2)){ //断开该连接
info.s_client->Close();
delete info.s_client;
info.s_client=NULL;
s_info.RemoveAt(s_info.FindIndex(id)); //从链表中删除该结构体
AfxMessageBox("Disconnect successfully!");