服务器

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    server=new QTcpServer(this);
}

Widget::~Widget()
{
    delete ui;
}


void Widget::on_pushButton_clicked()
{
    quint16 port=ui->lineEdit->text().toUInt();
    if(!server->listen(QHostAddress::Any,port))
    {
        QMessageBox::critical(this,"错误","服务器启动失败");
        return;
    }else
    {
        QMessageBox::information(this,"成功","服务器启动成功");
    }
    connect(server,&QTcpServer::newConnection,this,&Widget::newConnection_slot);
}

void Widget::newConnection_slot()
{
    QTcpSocket *s;
    s=server->nextPendingConnection();
    list.push_back(s);
    connect(s,&QTcpSocket::readyRead,this,&Widget::readyRead_sloat);
}

void Widget::readyRead_sloat()
{
    for(int i=0;i<list.count();i++)
    {
        if(!list[i]->state())
        {
            list.removeAt(i);
        }
    }
    for(int i=0;i<list.count();i++)
    {
        if(list[i]->bytesAvailable())
        {
            QByteArray msg=list[i]->readAll();
            ui->listWidget->addItem(QString::fromLocal8Bit(msg));
            for(int j=0;j<list.count();j++)
            {
                list[j]->write(msg);
            }
        }
    }
}

客户端

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    connect(socket,&QTcpSocket::connected,this,&Widget::connected_slot);
    connect(socket,&QTcpSocket::readyRead,this,&Widget::readtRead_slot);

}

Widget::~Widget()
{
    delete ui;
}


void Widget::on_lj_btn_clicked()
{
    username=ui->name_edit->text();
    quint16 port=ui->port_edit->text().toUInt();
    QString ipname=ui->ip_edit->text();
    socket->connectToHost(ipname,port);
}

void Widget::connected_slot()
{
    QString s=username+"上线";
    socket->write(s.toLocal8Bit());
    QMessageBox::information(this,"成功","连接成功");
   }

void Widget::readtRead_slot()
{
    QByteArray s=socket->readAll();
    ui->listWidget->addItem(QString::fromLocal8Bit(s));
}

void Widget::on_fs_btn_clicked()
{
    QString s=username+":"+ui->xx_edit->text();
    socket->write(s.toLocal8Bit());
    ui->xx_edit->clear();
}

void Widget::on_dk_btn_clicked()
{
    QString s=username+"退出聊天室";
    socket->write(s.toLocal8Bit());
    socket->disconnectFromHost();
    QMessageBox::information(this,"退出","成功断开");
}