一. C语言中

1. 服务器端流程Server

        1. 创建套接字--socket()

        2.将套接字与其ip地址，端口号进行绑定--bind()

        3. 将套接字设置成被动监听状态--listen()

        2和3是Qt中的listen()，1，2和3实质就是把自己的信息固定下来，等待别人与之通信

        4. 阻塞等待客户端的连接请求--accept()

        5. 进行通信 1)recv(),read()接收数据 send() write()发送数据

        6. 关闭套接字--close()

2. 客户端流程Client

        1. 创建套接字--socket()

        绑定ip及端口号(可选)，此步可以随机让系统产生.

        2. 发送客户端的连接请求--connect()

        3, 进行通信 recv() read() 接收数据

        send() write() 发送数据

        4. 关闭套接字--close()

二. Qt中

1. 服务器端流程Server

1. 创建套接字服务器 QTcpServer 对象

2. 通过 QTcpServer 对象设置监听，即:QTcpServer::listen()

3. 基于 qTcpserver::newconnection()信号检测是否有新的客户端连接

4. 如果有新的客户端连接调用 QTcpSocket *QTcpserver::nextPendingconnection()得到通信的套接字对象

5. 使用通信的套接字对象 QTcpSocket和客户端进行通信

   #include "widget.h"
   #include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
   {ui->setupUi(this);this->setWindowTitle("服务器");server = new QTcpServer(this);connect(server,&QTcpServer::newConnection,[=](){socket = server->nextPendingConnection();ui->checkroomTex->append("与客户建立了联接...");connect(socket,&QTcpSocket::readyRead,[=](){QString recMeg = socket->readAll();ui->checkroomTex->append("客户端输出:"+recMeg);});connect(socket,&QTcpSocket::disconnected,[=](){ui->checkroomTex->append("客户端断开了连接");socket->deleteLater();});});
   }Widget::~Widget()
   {delete ui;
   }void Widget::on_startBtn_clicked()
   {int port = ui->port->text().toInt();server->listen(QHostAddress::Any,port);ui->startBtn->setEnabled(false);}void Widget::on_senderBtn_clicked()
   {QString sendMsg = ui->senderTex->toPlainText();socket->write(sendMsg.toUtf8());ui->checkroomTex->append("服务器端输出："+sendMsg);ui->senderTex->clear();
   }
   

2. 客户端流程Client

        1)创建通信的套接字类QTcpSocket对象

        2)使用服务器端绑定的IP和端口连接服务器QAbstractSocket::connectToHost()

        3)使用QTcpSocket对象和服务器进行通信

#include "widget.h"
#include "ui_widget.h"
#include <QHostAddress>
Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);this->setWindowTitle("客户端");//建立套接字socket = new QTcpSocket(this);//确认是否已经连接成功connect(socket,&QTcpSocket::connected,[=](){ui->checkroomTex->append("与服务器连接成功");});connect(socket,&QTcpSocket::readyRead,[=](){QString recMsg = socket->readAll();ui->checkroomTex->append("服务器输出"+recMsg);});connect(socket,&QTcpSocket::disconnected,[=](){ui->checkroomTex->append("服务器断开了");ui->linkserverBtn->setEnabled(true);ui->disconnectBtn->setEnabled(false);});
}Widget::~Widget()
{delete ui;
}void Widget::on_linkserverBtn_clicked()
{QString ip = ui->address->text();unsigned int port = ui->port->text().toUInt();socket->connectToHost(QHostAddress(ip),port);ui->linkserverBtn->setEnabled(false);ui->disconnectBtn->setEnabled(true);}void Widget::on_senderBtn_clicked()
{QString sendMsg = ui->senderTex->toPlainText();socket->write(sendMsg.toUtf8());ui->checkroomTex->append("客户端输出"+sendMsg);ui->senderTex->clear();
}void Widget::on_disconnectBtn_clicked()
{socket->close();ui->linkserverBtn->setEnabled(true);ui->disconnectBtn->setEnabled(false);
}