本章是入門章節,講解如何實現一個附帶界面的服務器,后續會完善與優化
- 使用qt編譯libevent
- 源碼
- 演示視頻
- qt的一些知識

1.主要功能有登錄界面
2.基于libevent實現的服務器的業務功能
使用qt編譯libevent
下載這個,其他版本也可以
主要是github上下載,可能有點卡
鏈接: link
編譯流程
1.打開qt然后點下面的紅框
2.選cmakelist
3.選編譯器
4.最后一步編譯
5.編譯成功后庫的位置
最后編譯成功后可以丟到/usr/bin里也可以丟到自己的寫的程序的目錄下
源碼
源碼結構如下
下面是libeventuse.cpp
#include "libeventuse.h"
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <signal.h>
#ifndef _WIN32
#include <netinet/in.h>
# ifdef _XOPEN_SOURCE_EXTENDED
# include <arpa/inet.h>
# endif
#include <sys/socket.h>
#endif#include <event2/bufferevent.h>
#include <event2/buffer.h>
#include <event2/listener.h>
#include <event2/util.h>
#include <event2/event.h>
#include"qdebug.h"static const char MESSAGE[] = "Hello, World!\n";static const unsigned short PORT = 9995;static void listener_cb(struct evconnlistener *, evutil_socket_t,struct sockaddr *, int socklen, void *);
static void conn_writecb(struct bufferevent *, void *);
static void conn_eventcb(struct bufferevent *, short, void *);
static void signal_cb(evutil_socket_t, short, void *);int main3()
{struct event_base *base;struct evconnlistener *listener;struct event *signal_event;struct sockaddr_in sin = {0};base = event_base_new();//初始化if (!base) {fprintf(stderr, "Could not initialize libevent!\n");return 1;}sin.sin_family = AF_INET;sin.sin_port = htons(PORT);listener = evconnlistener_new_bind(base, listener_cb, (void *)base,LEV_OPT_REUSEABLE|LEV_OPT_CLOSE_ON_FREE, -1,(struct sockaddr*)&sin,sizeof(sin));//事件監聽if (!listener) {fprintf(stderr, "Could not create a listener!\n");return 1;}signal_event = evsignal_new(base, SIGINT, signal_cb, (void *)base);//信號事件if (!signal_event || event_add(signal_event, NULL)<0) {fprintf(stderr, "Could not create/add a signal event!\n");return 1;}event_base_dispatch(base);//啟動evconnlistener_free(listener);event_free(signal_event);event_base_free(base);printf("done\n");return 0;
}static void
listener_cb(struct evconnlistener *listener, evutil_socket_t fd,struct sockaddr *sa, int socklen, void *user_data)
{struct event_base *base = static_cast<event_base*>(user_data);struct bufferevent *bev;bev = bufferevent_socket_new(base, fd, BEV_OPT_CLOSE_ON_FREE);if (!bev) {fprintf(stderr, "Error constructing bufferevent!");event_base_loopbreak(base);return;}bufferevent_setcb(bev, NULL, conn_writecb, conn_eventcb, NULL);bufferevent_enable(bev, EV_WRITE);bufferevent_disable(bev, EV_READ);bufferevent_write(bev, MESSAGE, strlen(MESSAGE));
}static void
conn_writecb(struct bufferevent *bev, void *user_data)
{struct evbuffer *output = bufferevent_get_output(bev);if (evbuffer_get_length(output) == 0) {printf("flushed answer\n");bufferevent_free(bev);}
}static void
conn_eventcb(struct bufferevent *bev, short events, void *user_data)
{if (events & BEV_EVENT_EOF) {printf("Connection closed.\n");} else if (events & BEV_EVENT_ERROR) {printf("Got an error on the connection: %s\n",strerror(errno));/*XXX win32*/}/* None of the other events can happen here, since we haven't enabled* timeouts */bufferevent_free(bev);
}static void
signal_cb(evutil_socket_t sig, short events, void *user_data)
{struct event_base *base = static_cast<event_base*>(user_data);struct timeval delay = { 2, 0 };printf("Caught an interrupt signal; exiting cleanly in two seconds.\n");event_base_loopexit(base, &delay);
}
libeventuse::libeventuse()
{main3();
}
下面是mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "ui_form.h"
#include"QString"
#include"qdebug.h"
#include"qmessagebox.h"
#include"libeventuse.h"#include <QMutex>
#include <QTime>
#include <QWidget>WorkThread::WorkThread(QObject *parent) : QThread(parent) {}void WorkThread::run() { // 必須實現 run()
libeventuse tmp;
emit this->server_finish();
}MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow)
{ui->setupUi(this);login_win=new Form;workthread=new WorkThread;login_win->hide();//登錄窗口打開workthread->start();connect(this->workthread,&WorkThread::server_finish,[=](){qDebug()<<"服務器關閉";});connect(this->workthread,&WorkThread::finished,this->workthread,&QObject::deleteLater);connect(this->login_win,&Form::back,[=](){//槽函數this->show();//返回登錄界面this->login_win->hide();//主執行界面關閉});}MainWindow::~MainWindow()
{delete login_win;delete ui;
}Form::Form(QWidget *parent) :QWidget(parent),ui(new Ui::Form)
{ui->setupUi(this);}Form::~Form()
{delete ui;
}void MainWindow::on_pushButton_clicked()
{QString RootName=ui->rootName->text();QString Password=ui->password->text();if(RootName.size()==0){QMessageBox::information(this, tr("提示"), tr("用戶名沒有輸入"));return ;}else if(RootName.size()==0){QMessageBox::information(this, tr("提示"), tr("密碼沒有輸入"));}if(RootName=="i"&&Password=="1")//驗證用戶和密碼{qDebug()<<RootName<<Password;login_win->show();//主執行界面打開this->hide();//登錄界面關閉}else{QMessageBox::information(this, tr("提示"), tr("用戶或密碼輸入錯誤"));}}void Form::on_pushButton_clicked()
{emit this->back();//發送信號
}void MainWindow::on_pushButton_2_clicked()
{}
下面是libeventuse.h
#ifndef LIBEVENTUSE_H
#define LIBEVENTUSE_H
class libeventuse
{
public:libeventuse();
};#endif // LIBEVENTUSE_H
下面是mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>
namespace Ui {
class Form;
}class Form : public QWidget
{Q_OBJECTpublic:explicit Form(QWidget *parent = 0);~Form();private slots:void on_pushButton_clicked();
signals:void back();
private:Ui::Form *ui;
};#include <QThread>
class WorkThread : public QThread {Q_OBJECT // 必須添加!!!
public:explicit WorkThread(QObject *parent = nullptr);
protected:void run() override; // 虛函數聲明
signals:
void WorkThread_signal(int b);//自定義的信號
void server_finish();
};namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = 0);~MainWindow();Form* login_win=nullptr;WorkThread*workthread=nullptr;
private slots:void on_pushButton_clicked();void on_pushButton_2_clicked();private:Ui::MainWindow *ui;
};#endif // MAINWINDOW_H
pro文件的配置
演示視頻
20250415_153450
我視頻第一部分展示了如何在qt創建窗口
視頻第二部分展示了客戶端連接到服務器后會接收到hello world
視頻等審核過了我再放上來
審核沒過我就發效果圖
qt的一些知識
1.信號的格式
signals:
void WorkThread_signal(int b);//自定義的信號
2.注意事項,需要分寫入Q_OBJECT才能這么定義
3.信號發送使用 emit 發送
4.使用connect槽函數來綁定信號要處理的邏輯