#include "tcpserver.h"
#include "ui_tcpserver.h"

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

    //1.创建服务器套接字对象
    m_tcpServer = new QTcpServer(this);
    //2.设置为监听模式
    m_tcpServer->listen(QHostAddress::Any,5200);

    //3.通过信号接收客户端的请求
    connect(m_tcpServer, SIGNAL(newConnection()),this,SLOT(slotNewConnection()));

}

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

void TcpServer::slotNewConnection()
{
    //4.处理客户端请求
    m_tcpSocket = m_tcpServer->nextPendingConnection();

    //5.发送数据
    m_tcpSocket->write("connect success!");

    //6.连接信号，接受客户端数据
    connect(m_tcpSocket,SIGNAL(readyRead()),this,SLOT(slotReadyRead()));

}

void TcpServer::slotReadyRead()
{
    QString data = m_tcpSocket->readAll();

    ui->textEdit_receiver->append(data);
}

void TcpServer::on_pushButton_send_clicked()
{
    QString sendData = ui->textEdit_send->toPlainText();

    m_tcpSocket->write(sendData.toLatin1());
}

三： 客户端

客户端通过使用Qt提供的QTcpSocket类可以方便的实现与服务器端的通信：

#ifndef TCPCLIENT_H
#define TCPCLIENT_H

#include <QWidget>
#include <QTcpSocket>

namespace Ui {
class TcpClient;
}

class TcpClient : public QWidget
{
    Q_OBJECT

public:
    explicit TcpClient(QWidget *parent = 0);
    ~TcpClient();

private slots:
    void slotReadyRead();

    void on_pushButton_send_clicked();

private:
    Ui::TcpClient *ui;
    QTcpSocket *m_tcpClient;
};

#endif // TCPCLIENT_H

#include "tcpclient.h"
#include "ui_tcpclient.h"
#include <QHostAddress>

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

    //1.创建套接字
    m_tcpClient = new QTcpSocket(this);

    //2.连接服务器
    m_tcpClient->connectToHost(QHostAddress("127.0.0.1"),5200);

    //3.通过信号接收服务器数据
    connect(m_tcpClient, SIGNAL(readyRead()), this, SLOT(slotReadyRead()));
}

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

void TcpClient::slotReadyRead()
{
    QString data = m_tcpClient->readAll();

    ui->textEdit_receiver->append(data);
}


void TcpClient::on_pushButton_send_clicked()
{
    QString sendData = ui->textEdit_send->toPlainText();

    m_tcpClient->write(sendData.toLatin1());
}