簡易網絡聊天室服務端.PNG

簡易網絡聊天室客戶端.PNG

一、服務端

（一）創建套接字進行監聽

    //創建套接字 socket()
    server = new QTcpServer(this);

    //監聽，端口號：9999   bind(...), listen()
    bool isOk = server->listen(QHostAddress::Any,9999);

    //監聽失敗
    if(false == isOk)
    {
        QMessageBox::warning(this,"監聽","監聽失敗");
        return;
    }

    //當有客戶端鏈接時，觸發信號：newConnection()
    connect(server,SIGNAL(newConnection()),this,SLOT(newClient()));

（二）連接客戶端

void Server::newClient()
{
    QTcpSocket *client;

    //取出鏈接套接字   accept()
    client = server->nextPendingConnection();

    connect(client,SIGNAL(readyRead()),this,SLOT(tcpRead()));
    connect(client,SIGNAL(disconnected()),this,SLOT(disClient()));
    clients.push_back(client);
}

（三）讀取信息并群發

void Server::tcpRead()
{
    //哪一個QTcpSocketc對象可讀就會發出readyRead()信號，通過信號的發出者找到相應的對象
    QTcpSocket *client = qobject_cast<QTcpSocket *>(sender());
    QString time = QDateTime::currentDateTime().toString("yyyy-MM-dd hh:mm:ss");
    QString str = QHostAddress(client->peerAddress().toIPv4Address()).toString() + ": " + time;
    ui->MessageBrowser->append(str);
    ui->MessageBrowser->append(client->readAll());

    //群發
    QList<QTcpSocket *>::iterator it;
    for(it = clients.begin();it != clients.end();it++)
        (*it)->write(str.toUtf8());
}

（四）退出客戶端

void Server::disClient()
{
    QTcpSocket *client = qobject_cast<QTcpSocket *>(sender());
    clients.removeOne(client);
}

二、客戶端

（一）連接服務器

Client::Client(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Client)
{
    ui->setupUi(this);

    tcp = new QTcpSocket(this);
    tcp->connectToHost("127.0.0.1",9999);
    if(!tcp->waitForConnected(3000))
    {
        QMessageBox::warning(this,"錯誤","連接失敗");
        return;
    }

    connect(tcp,SIGNAL(readyRead()),this,SLOT(tcpRead()));
    connect(ui->sendpushButton,SIGNAL(clicked(bool)),this,SLOT(tcpSend()));
}

（二）讀取信息

void Client::tcpRead()
{
    QString str;

    str = tcp->readAll();
    ui->textBrowser->append(str);
    ui->textBrowser->moveCursor(QTextCursor::End);
    ui->textBrowser->append(ui->sendlineEdit->text());
}

（三）發送信息

void Client::tcpSend()
{
    QString str = ui->sendlineEdit->text();
    tcp->write(str.toUtf8());
}

該聊天系統能實現群聊功能，即一個客戶端向服務器發送信息，服務器接受信息之后將接受的信息發給所有與服務器相連的客戶端。