智能家居设备状态监测与建议系统：基于C++和Qt的服务器-客户端架构实现
<p>#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <arpa/inet.h>
#include <sqlite3.h>
#include <netinet/in.h></p>
<p>#define MAX_BUFFER_SIZE 1024</p>
<p>typedef struct {
int uid;
char device_name[20];
char device_state[20];
char value[20];
char mode[20];
} Status;</p>
<p>typedef struct {
int sockfd;
struct sockaddr_in client_addr;
socklen_t client_addr_len;
sqlite3 *db;
} ServerContext;</p>
<p>void handleClientRequest(ServerContext *context) {
char buffer[MAX_BUFFER_SIZE];
int userid;</p>
<pre><code>// 接收客户端发送的userid
ssize_t recvSize = recv(context->sockfd, &userid, sizeof(int), 0);
if (recvSize == -1) {
perror("userid接受失败\nrecv");
return;
} else if (recvSize == 0) {
perror("客户端已关闭连接");
return;
} else if (recvSize != sizeof(int)) {
perror("接收到的字节数不正确");
return;
}
userid = ntohl(userid); // 将网络字节序转换为主机字节序
printf("客户端已连接\n");
printf("userid:%d\n", userid);
// 查询数据库获取设备状态信息
char sql[100];
snprintf(sql, sizeof(sql), "SELECT * FROM Status WHERE uid = %d", userid);
sqlite3_stmt *stmt = NULL;
int rc = sqlite3_prepare_v2(context->db, sql, -1, &stmt, NULL);
if (rc != SQLITE_OK) {
fprintf(stderr, "无法执行的语句: %s\n", sqlite3_errmsg(context->db));
return;
}
Status status;
memset(&status, 0, sizeof(Status)); // 清空status结构体
while (sqlite3_step(stmt) == SQLITE_ROW) {
status.uid = sqlite3_column_int(stmt, 1);
const unsigned char *device_name = sqlite3_column_text(stmt, 2);
if (device_name != NULL) {
strncpy(status.device_name, device_name, sizeof(status.device_name)-1);
status.device_name[sizeof(status.device_name)-1] = '\0';
}
const unsigned char *device_state = sqlite3_column_text(stmt, 3);
if (device_state != NULL) {
strncpy(status.device_state, device_state, sizeof(status.device_state)-1);
status.device_state[sizeof(status.device_state)-1] = '\0';
}
const unsigned char *value = sqlite3_column_text(stmt, 4);
if (value != NULL) {
strncpy(status.value, value, sizeof(status.value)-1);
status.value[sizeof(status.value)-1] = '\0';
}
const unsigned char *mode = sqlite3_column_text(stmt, 5);
if (mode != NULL) {
strncpy(status.mode, mode, sizeof(status.mode)-1);
status.mode[sizeof(status.mode)-1] = '\0';
}
}
sqlite3_finalize(stmt); // 释放查询结果集
if (strlen(status.device_name) == 0) {
perror("接收设备状态信息失败");
return;
}
// 分析设备状态并生成建议
char suggestion[MAX_BUFFER_SIZE];
if (strcmp(status.device_name, "空调") == 0) {
int temperature = atoi(status.value);
if (temperature < 24) {
snprintf(suggestion, sizeof(suggestion), "空调温度过低，建议提高温度至26℃");
} else {
snprintf(suggestion, sizeof(suggestion), "空调温度正常");
}
} else if (strcmp(status.device_name, "加湿器") == 0) {
int humidity = atoi(status.value);
if (humidity < 40 || humidity > 70) {
snprintf(suggestion, sizeof(suggestion), "加湿器湿度过高或过低，建议调整加湿器湿度");
} else {
snprintf(suggestion, sizeof(suggestion), "加湿器湿度正常");
}
} else {
snprintf(suggestion, sizeof(suggestion), "设备状态未知");
}
// 向客户端发送建议
ssize_t sendSize = send(context->sockfd, suggestion, strlen(suggestion), 0);
if (sendSize == -1) {
perror("发送失败\nsend");
return;
}
else{
printf("发送成功!");
}
printf("%s\n", suggestion);
</code></pre>
<p>}</p>
<p>int main() {
printf("正在连接中...\n");
int sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd == -1) {
perror("连接失败\nsocket");
return 1;
}</p>
<pre><code>struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = INADDR_ANY;
server_addr.sin_port = htons(12345);
if (bind(sockfd, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {
perror("连接失败\nbind");
close(sockfd);
return 1;
}
if (listen(sockfd, 5) == -1) {
perror("连接失败\nlisten");
close(sockfd);
return 1;
}
sqlite3 *db;
int rc = sqlite3_open("/mnt/g/Qt/Client/Smarthome_Client/database/database.db", &db);
if (rc != SQLITE_OK) {
fprintf(stderr, "数据库打开失败: %s\n", sqlite3_errmsg(db));
return 1;
}
ServerContext context;
context.sockfd = sockfd;
context.client_addr_len = sizeof(context.client_addr);
context.db = db;
fd_set readfds;
int maxfd = sockfd;
while (1) {
FD_ZERO(&readfds);
FD_SET(sockfd, &readfds);
int activity = select(maxfd + 1, &readfds, NULL, NULL, NULL);
if (activity == -1) {
perror("select");
break;
}
if (FD_ISSET(sockfd, &readfds)) {
int clientSockfd = accept(sockfd, (struct sockaddr *)&context.client_addr, &context.client_addr_len);
if (clientSockfd == -1) {
perror("套接字接收失败\naccept");
break;
}
context.sockfd = clientSockfd;
handleClientRequest(&context);
close(clientSockfd);
}
}
sqlite3_close(db);
close(sockfd);
printf("服务器已关闭\n");
return 0;
</code></pre>
<p>}</p>
<p>#include "procession.h"
#include "ui_procession.h"
#include <QAbstractSocket>
#include <QDebug></p>
<p>Procession::Procession(int userid,QWidget *parent) :
QWidget(parent),
ui(new Ui::Procession),
userid(userid)
{
ui->setupUi(this);
processionWidget();
m_socket = new QTcpSocket(this);
//connect(ui->connectBtn, &QPushButton::clicked, this, &Procession::on_connectBtn_clicked);
connect(m_socket, &QTcpSocket::readyRead, this, &Procession::readyRead);
connect(m_socket, &QTcpSocket::connected, this, &Procession::connected);
connect(m_socket, &QTcpSocket::disconnected,this,&Procession::disconnected);
connect(m_socket, QOverload<a href="QAbstractSocket::SocketError">QAbstractSocket::SocketError</a>::of(&QTcpSocket::error), this, &Procession::displayError);
}</p>
<p>Procession::~Procession()
{
delete ui;
// 在程序结束前关闭套接字
m_socket->close();
}</p>
<p>void Procession::processionWidget()
{
setWindowTitle("服务器通信");
setAutoFillBackground(true);
QPalette palette=this->palette();
QPixmap pixmap(":/user/image/image/net.jpg");
palette.setBrush(QPalette::Window, QBrush(pixmap));
setPalette(palette);
setFixedSize(600,400);
}</p>
<p>void Procession::connected()
{
ui->message->append("连接成功");
QByteArray block;
QDataStream out(&block, QIODevice::WriteOnly);
out << static_cast<quint32>(this->userid);
qDebug()<<static_cast<quint32>(this->userid);
if (m_socket->write(block) == -1) {
ui->message->append("发送userid失败");
m_socket->close();
}
//m_socket->close(); // 关闭套接字
}</p>
<p>void Procession::disconnected()
{
ui->message->append("连接失败");
m_socket->close();
}</p>
<p>void Procession::readyRead()
{
QByteArray data = m_socket->readAll();
if (data.isEmpty()) {
ui->message->append("读取的数据为空");
return;
}
// 解析服务器返回的数据
QDataStream in(&data, QIODevice::ReadOnly);
QString suggestion;
in >> suggestion; // 使用重载的 >> 运算符来读取数据
if (in.status() != QDataStream::Ok) {
ui->message->append("解析服务器返回的数据失败");
return;
}
ui->message->append(suggestion);
//m_socket->close();
}</p>
<p>void Procession::displayError(QAbstractSocket::SocketError error)
{
QString errorMessage;
switch (error) {
case QAbstractSocket::ConnectionRefusedError:
errorMessage = "连接被拒绝";
break;
case QAbstractSocket::RemoteHostClosedError:
errorMessage = "远程主机关闭";
break;
case QAbstractSocket::HostNotFoundError:
errorMessage = "未找到主机";
break;
case QAbstractSocket::SocketTimeoutError:
errorMessage = "连接超时";
break;
case QAbstractSocket::NetworkError:
errorMessage = "网络错误";
break;
default:
errorMessage = "未知错误";
break;
}
ui->message->append("连接失败：" + errorMessage);
}</p>
<p>void Procession::on_connectBtn_clicked()
{
if (m_socket->state() == QAbstractSocket::ConnectedState) {
m_socket->disconnectFromHost(); // 先关闭套接字
}</p>
<pre><code>ui->message->append("已经连接上服务器");
QString ip = ui->IP->text();
QString port = ui->port->text();
if (ip.isEmpty() || port.isEmpty()) {
ui->message->clear();
ui->message->append("请输入有效的IP地址和端口号");
return;
}
ui->message->clear();
ui->message->append("正在连接中...");
m_socket->connectToHost(ip, static_cast<quint16>(ui->port->text().toInt()));
</code></pre>
<p>}</p>
<p>#include <QWidget>
#include <QTcpSocket>
#include <QDebug>
#include <QByteArray>
#include <QTcpSocket></p>
<p>namespace Ui {
class Procession;
}</p>
<p>class Procession : public QWidget
{
Q_OBJECT</p>
<p>public:
explicit Procession(int userid,QWidget *parent = nullptr);
~Procession();
void processionWidget();</p>
<p>private slots:
//void on_pushButton_clicked();
void connected();
void disconnected();
void readyRead();
void displayError(QAbstractSocket::SocketError error);</p>
<pre><code>void on_connectBtn_clicked();
</code></pre>
<p>private:
Ui::Procession <em>ui;
int userid;
QTcpSocket</em> m_socket;
};</p>
<p>#endif // PROCESSION_H</p>
<p>客户端IP=127.0.0.1 Port=12345</p>
<p>root@WIN-K3C9KG85CB8:/home/SmartHome/Server# valgrind --leak-check=full ./main.exec
==3155== Memcheck, a memory error detector
==3155== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3155== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==3155== Command: ./main.exec
==3155==
正在连接中...
建议发送成功！客户端已连接
userid:123
空调温度正常</p>
<p>客户端运行结果
正在连接中...
连接成功
解析服务器返回的数据失败
连接失败：远程主机关闭
连接失败</p>
<p>ifconfig运行结果
root@WIN-K3C9KG85CB8:/home/SmartHome/Server# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.21.91.176 netmask 255.255.240.0 broadcast 172.21.95.255
inet6 fe80::215:5dff:fedd:6558 prefixlen 64 scopeid 0x20<link>
ether 00:15:5d:dd:65:58 txqueuelen 1000 (Ethernet)
RX packets 11543 bytes 15485605 (15.4 MB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2910 bytes 319768 (319.7 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0</p>
<p>lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 511 bytes 31391 (31.3 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 511 bytes 31391 (31.3 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0</p>
<p>如何解决</p>
<p>客户端地址已设置成172.21.91.176</p>
<p>服务器运行结果
root@WIN-K3C9KG85CB8:/home/SmartHome/Server# valgrind --leak-check=full ./main.exec
==3194== Memcheck, a memory error detector
==3194== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3194== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==3194== Command: ./main.exec
==3194==
正在连接中...
建议发送成功！客户端已连接
userid:123
空调温度正常</p>
<p>第二次点击客户端按键时服务器运行结果
客户端已连接
userid:123
空调温度正常
第三次点击客户端按键服务器运行结果
客户端已连接
userid:123
空调温度正常</p>
<p>客户端运行结果一直是下面这样
正在连接中...
连接成功
解析服务器返回的数据失败
连接失败：远程主机关闭
连接失败</p>
<p>客户端解析服务器发来的消息的代码
void Procession::readyRead()
{
QByteArray data = m_socket->readAll();
if (data.isEmpty()) {
ui->message->append("读取的数据为空");
return;
}
// 解析服务器返回的数据
QDataStream in(&data, QIODevice::ReadOnly);
QString suggestion;
in >> suggestion; // 使用重载的 >> 运算符来读取数据
if (in.status() != QDataStream::Ok) {
ui->message->append("解析服务器返回的数据失败");
return;
}
ui->message->append(suggestion);
m_socket->close();
}</p>
<p>客户端运行结果
正在连接中...
连接成功
连接失败</p>
<p>有什么问题，该如何解决内容：根据服务器运行结果和客户端运行结果，可以看出服务器成功接收到了客户端发送的userid，并成功发送了建议给客户端。但是客户端在解析服务器返回的数据时出现了问题，导致无法显示建议。</p>
<p>可能的问题是数据的读取方式不正确，或者数据的发送和接收顺序有问题。</p>
<p>建议检查以下几点：</p>
<ol>
<li>
<p>确保服务器端和客户端使用的数据流读写方式一致，例如都使用QDataStream的方式进行读写。</p>
</li>
<li>
<p>确保服务器端和客户端的数据发送和接收顺序一致，即先发送userid，再接收建议。</p>
</li>
<li>
<p>检查数据的读取方式是否正确，例如使用正确的数据类型进行读取。</p>
</li>
<li>
<p>可以在客户端的readyRead()函数中添加一些调试输出，打印接收到的数据，以便进一步排查问题。</p>
</li>
<li>
<p>可以尝试使用Wireshark等网络抓包工具，查看服务器和客户端之间的通信数据，以确定数据是否正确发送和接收。</p>
</li>
</ol>
<p>希望以上建议对您有帮助，如果问题仍然存在，请提供更多的代码和运行结果，以便进一步分析。</p>
原文地址: http://www.cveoy.top/t/topic/fCDA 著作权归作者所有。请勿转载和采集!