[C++知识库]基于Linux、QT、C++的点餐系统

基于Linux、QT、C++的点餐系统

一、功能实现

管理员及收银员的注册登录、人员信息管理、账单查看、餐品信息管理、顾客点餐、厨房上菜、收银结账。

二、项目描述

1、项目采用 C/S 架构，利用 TCP 协议进行通信，采用了多线程的方法解决服务端与多个客服端的通信。
2、通过vector容器来存放顾客的订单信息，顾客提交订单时，将容器发送给管理端和厨房。
3、通过MySQL数据库来储存用户信息、菜单信息、账单信息，及厨房待做餐品清单。
4、采用中介者模式和状态模式，实现不同客服端间的信息交互。
5、顾客提交订单后可随时进行加餐，对未上餐品可进行催餐和退餐。
6、收银员可查询相应桌号的消费详情和消费总额并进行结账。
7、管理员可进行对用户信息和菜单信息的修改、添加和删除，并可查看账单及账单详情。

三、界面展示

1、顾客端（客户端）

2、厨房端（客户端）
3、收银端（客户端）

4、管理端（服务端）

四、MySQL表数据

1、表

2、菜单

3、饮品

4、用户

5、餐桌状态

6、厨房待做菜品

7、账单

8、账单详情

五、代码展示

1、顾客端

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QSqlQuery>
#include <vector>
#include<QString>
#include<QTcpSocket>
#include "childdorm.h"
#include "structural.h"
using namespace std;
namespace Ui {
class Widget;
}

class childdorm;
class Widget : public QWidget
{
    Q_OBJECT


public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
    void Init();//初始化
    void client();//客服端
    void flag(QByteArray array);//标志位判断
    void Menu_print();//打印菜单
    void Chef_in(vector<MenuInfo> menuVec);//上菜
   // friend class childdorm;

    vector<FoodInfo>* getVecNo(){return &FoodVec_no;}
    vector<FoodInfo>* getVec(){return &FoodVec;}
    QTcpSocket * getsocket(){return tcpsocket;}
private slots:
    void on_pushButton_3_clicked();

    void on_pushButton_4_clicked();

    void on_pushButton_clicked();

    void on_pushButton_2_clicked();
    void comeback();//显示此窗口
    void Delete();//退餐
public:
    float m_sum;//总额
    Ui::Widget *ui;
    QSqlDatabase db;
    FoodInfo F_head;//订单结构体
    vector<FoodInfo> foodVec;//通用订单容器
    vector<FoodInfo> FoodVec;//订单容器
    vector<FoodInfo> FoodVec_no;//未上菜单容器
    vector<FoodInfo> FoodVec_in;//已上菜单容器
    QTcpSocket *tcpsocket;
    vector<MenuInfo> MenuVec;//菜单容器
    MenuInfo M_head;//菜单结构体
    childdorm *child ;
};



#endif // WIDGET_H

childdrom.h

#ifndef CHILDDORM_H
#define CHILDDORM_H

#include <QWidget>
#include<QDesktopWidget>
#include<QMessageBox>
#include<vector>
#include"widget.h"
#include "structural.h"
using namespace std;
namespace Ui {
class childdorm;
}

class Widget;

class childdorm : public QWidget
{
    Q_OBJECT
signals:
    void Interface();//显示父窗口
    void Inter_delete();//退餐
public:
    explicit childdorm(QWidget *parent = 0 );
    ~childdorm();
    void getvec(vector<FoodInfo> FoodVec_no,vector<FoodInfo> FoodVec_in);//打印订单
    void Delete_food();//退餐
    void getData(QWidget *parent);   //通过this把父窗口的指针传到子窗口当中
private slots:
    void on_pushButton_3_clicked();
    void on_pushButton_clicked();
    void on_pushButton_2_clicked();
    
private:
    Ui::childdorm *ui;
    FoodInfo F_head;//订单结构体
    vector<FoodInfo> *FoodVec_No;//未上菜单容器
    vector<FoodInfo> *FoodVec;//已上菜单容器
    vector<FoodInfo> DeleteVec;//退餐容器
    QTcpSocket *tcpsocket;
    Widget * p;
    //Widget *child;

};


#endif // CHILDDORM_H

structural.h

#ifndef STRUCTURAL_H
#define STRUCTURAL_H

typedef struct Food
{
    char table[5]; //桌号
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char quatity[10];//数量
    char post[200];//备注
}FoodInfo;

typedef struct Menu
{
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char state[20];//状态

}MenuInfo;


#endif // STRUCTURAL_H

main.cpp

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
     w.show();
    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include <QDesktopWidget>
#include<QSqlQuery>
#include<QDebug>
#include<QString>
#include<cstring>
#include<QMessageBox>
#include<QSqlError>
#include<QHostAddress>
#include<QTableWidgetItem>
#include <QVariant>
#include<unistd.h>
using namespace std;

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    ui->tabWidget->setTabText(0,"主餐");
    ui->tabWidget->setTabText(1,"饮品");
    this->setFixedSize(1500,800);//背景图尺寸
    this->setWindowTitle(QStringLiteral("点餐窗口"));
   // this->move(QPoint(100,100));
    this->setWindowIcon(QIcon(":/image/28.png"));//APP图标

    //居中显示
    QDesktopWidget* desktop = QApplication::desktop();
    move((desktop->width() - this->width())/2, (desktop->height() - this->height())/2);

    //add back picture
    QPalette pal = this->palette();
    //pal.setBrush(QPalette::Background,QBrush(QPixmap(":/image/27.jpg")));//背景图
    setPalette(pal);
    ui->lcdNumber->setSegmentStyle(QLCDNumber::Flat);

    //设置为只读模式
    ui->tableWidget->setEditTriggers(QAbstractItemView::NoEditTriggers);
    ui->tableWidget_2->setEditTriggers(QAbstractItemView::NoEditTriggers);
    ui->tableWidget_3->setEditTriggers(QAbstractItemView::NoEditTriggers);

    ui->tableWidget->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应
    ui->tableWidget_2->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应
    ui->tableWidget_3->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应

    Init();//初始化
    client();//客服端操作

    QStringList headtext2;
    headtext2<<"序号"<<"餐名"<<"价格"<<"数量"<<"备注";
    ui->tableWidget->setColumnCount(headtext2.count());//列表设置为和headtext相等
    ui->tableWidget->setHorizontalHeaderLabels(headtext2);//插入表头
    ui->tableWidget->setRowCount(0);
    m_sum = 0;

    child = new childdorm();
    child->hide();
    child->getData(this);   //通过this把父窗口的指针传到子窗口当中
    connect(child,SIGNAL(Interface()),this,SLOT(comeback()));//信号槽
    connect(child,SIGNAL(Inter_delete()),this,SLOT(Delete()));//信号槽
}

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

void Widget::Init()//初始化
{
    tcpsocket = new QTcpSocket(this);//创建客户端套接字


    connect(tcpsocket,&QTcpSocket::connected,//请求连接信号
           [=]()
    {
        //ui->textEdit->setText("成功连接服务器");
    }
    );

    QString ip = "192.168.12.13";
    qint16 port = 8888;
    tcpsocket->connectToHost(QHostAddress(ip),port);

    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"order");  //放入标志位
    strcpy(F_head.price,"\0");
    strcpy(F_head.price,"\0");
    strcpy(F_head.post,"\0");
    FoodVec.push_back(F_head);//订单信息标志位放入容器中首元素

    strcpy(F_head.food,"order_up");  //放入标志位
    FoodVec_no.push_back(F_head);//订单信息标志位放入容器中首元素
}

void Widget::client()        //客服端操作
{
    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"menu");  //放入标志位
    strcpy(F_head.price,"\0");
    strcpy(F_head.price,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);//订单信息标志位放入容器中首元素
    QByteArray a1;
    a1.resize(sizeof(FoodInfo)*foodVec.size());
    memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
    tcpsocket->write(a1);


    connect(tcpsocket,&QTcpSocket::readyRead,
            [=]()
    {
        QByteArray array = tcpsocket->readAll();
        flag(array);     //数据解析
    }
    );
}

void Widget::flag(QByteArray array) //服务端信息判断
{
    vector<MenuInfo> menuVec; //菜单容器
    menuVec.resize(array.size()/sizeof(MenuInfo));
    memcpy(menuVec.data(),array.data(),array.size());
    qDebug()<<menuVec[0].food;
    if(strcmp(menuVec[0].food,"menu")==0)
    {
        MenuVec = menuVec;
        Menu_print();
    }
    else if(strcmp(menuVec[0].food,"chef_in")==0)
    {
        Chef_in(menuVec);
    }

}

void Widget::Chef_in(vector<MenuInfo> menuVec)//上菜
{
    for(int i = 0; i < FoodVec_no.size(); i++)
    {
        if(strcmp(FoodVec_no[i].number,menuVec[1].number) == 0)
        {
            strcpy(F_head.table,FoodVec_no[i].table);
            strcpy(F_head.number,FoodVec_no[i].number);
            strcpy(F_head.food,FoodVec_no[i].food);
            strcpy(F_head.price,FoodVec_no[i].price);
            strcpy(F_head.quatity,FoodVec_no[i].quatity);
            strcpy(F_head.post,FoodVec_no[i].post);
            FoodVec_in.push_back(F_head);//将上菜信息放入已上菜单容器中
            FoodVec_no.erase(FoodVec_no.begin ()+i);//删除未上菜单中该元素
        }
    }
    for(int i = 1; i < FoodVec.size(); i++)
    {
        if(strcmp(FoodVec[i].number,menuVec[1].number) == 0)
        {
            strcpy(FoodVec[i].table,"0");
        }
    }
    child->getvec(FoodVec_no,FoodVec_in);
}

void Widget::Menu_print()//打印菜单
{
    QStringList headtext;
    headtext<<"序号"<<"餐名"<<"价格"<<"状态";
    ui->tableWidget_2->setColumnCount(headtext.count());     //列表设置为和headtext相等
    ui->tableWidget_2->setHorizontalHeaderLabels(headtext);  //插入表头
    ui->tableWidget_2->setRowCount(0);

    QStringList headtext1;
    headtext1<<"序号"<<"饮品名"<<"价格"<<"状态";
    ui->tableWidget_3->setColumnCount(headtext1.count());    //列表设置为和headtext相等
    ui->tableWidget_3->setHorizontalHeaderLabels(headtext1); //插入表头
    ui->tableWidget_3->setRowCount(0);

    for (int j=1;j< MenuVec.size();j++)
    {
        QString temp = QString(MenuVec[j].number);
        int number = temp.toInt();
        if( number < 20000)
        {
            int rowcount = ui->tableWidget_2->rowCount();
            ui->tableWidget_2->insertRow(rowcount);
            QTableWidgetItem *column = new QTableWidgetItem(MenuVec[j].number);
            QTableWidgetItem *column1 = new QTableWidgetItem(MenuVec[j].food);
            QTableWidgetItem *column2 = new QTableWidgetItem(MenuVec[j].price);
            QTableWidgetItem *column3 = new QTableWidgetItem(MenuVec[j].state);

            ui->tableWidget_2->setItem(rowcount,0,column);
            ui->tableWidget_2->setItem(rowcount,1,column1);
            ui->tableWidget_2->setItem(rowcount,2,column2);
            ui->tableWidget_2->setItem(rowcount,3,column3);
        }
        else
        {
            int rowcount = ui->tableWidget_3->rowCount();
            ui->tableWidget_3->insertRow(rowcount);
            QTableWidgetItem *column = new QTableWidgetItem(MenuVec[j].number);
            QTableWidgetItem *column1 = new QTableWidgetItem(MenuVec[j].food);
            QTableWidgetItem *column2 = new QTableWidgetItem(MenuVec[j].price);
            QTableWidgetItem *column3 = new QTableWidgetItem(MenuVec[j].state);

            ui->tableWidget_3->setItem(rowcount,0,column);
            ui->tableWidget_3->setItem(rowcount,1,column1);
            ui->tableWidget_3->setItem(rowcount,2,column2);
            ui->tableWidget_3->setItem(rowcount,3,column3);
        }
     }
}

void Widget::on_pushButton_3_clicked()//提交订单
{
    QString S = ui->lineEdit->text(); //桌号
    char s[5];
    QByteArray ba = S.toLocal8Bit();
    memcpy(s,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

    if(S == "\0")
    {
        QMessageBox::warning(this,"提示!","请填写桌号!");
    }
    else
    {
       // qDebug()<< MenuVec[0].food;
        strcpy(FoodVec[0].table,s);
        int rowcount = ui->tableWidget->rowCount();//总行数
        for (int j=0;j<rowcount;j++)
        {
            QString str = ui->tableWidget->item(j,0)->text(); //获取序号
            QString str1 = ui->tableWidget->item(j,1)->text();//获取菜名
            QString str2 = ui->tableWidget->item(j,2)->text();//获取价格
            QString str3 = ui->tableWidget->item(j,3)->text();//获取价格
            QString str4 = ui->tableWidget->item(j,4)->text();//获取备注

            strcpy(F_head.table,s);
            ba = str.toLocal8Bit();
            memcpy(F_head.number,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str1.toLocal8Bit();
            memcpy(F_head.food,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str2.toLocal8Bit();
            memcpy(F_head.price,ba.data(),ba.size()+1);   //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str3.toLocal8Bit();
            memcpy(F_head.quatity,ba.data(),ba.size()+1); //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str4.toLocal8Bit();
            memcpy(F_head.post,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

            FoodVec.push_back(F_head);//菜品信息放入容器中
            FoodVec_no.push_back(F_head);//菜品信息放入未上菜单容器中
        }

        this->hide();
        child->getvec(FoodVec_no,FoodVec_in);
        child->show();

        //向服务端发送订单信息
        QByteArray a1;
        a1.resize(sizeof(FoodInfo)*FoodVec.size());
        memcpy(a1.data(),FoodVec.data(),sizeof(FoodInfo)*FoodVec.size());
        tcpsocket->write(a1);
    }

}

void Widget::on_pushButton_4_clicked()//退出
{
    exit(-1);
}

void Widget::on_pushButton_clicked()//添加菜品
{
    int flag = 0;
    char number[10];
    QString s = ui->lineEdit_2->text();//餐品序号
    QByteArray ba = s.toLocal8Bit();
    memcpy(number,ba.data(),ba.size()+1);//加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
    QTableWidgetItem *column = new QTableWidgetItem(s);
    QString s1;
    QString s2;
    for(int i = 0; i < MenuVec.size(); i++)
    {
        if(strcmp(MenuVec[i].number,number) == 0)
        {
            s1 = QString(MenuVec[i].food);
            s2 = QString(MenuVec[i].price);
            flag = 1;
        }
    }

    QTableWidgetItem *column1 = new QTableWidgetItem(s1);

    QTableWidgetItem *column2 = new QTableWidgetItem(s2);

    QString s3 = ui->lineEdit_3->text();//餐品数量
    QTableWidgetItem *column3 = new QTableWidgetItem(s3);

    QString s4 = ui->lineEdit_4->text();//备注
    QTableWidgetItem *column4 = new QTableWidgetItem(s4);

    if(flag == 1)
    {
        int rowcount = ui->tableWidget->rowCount();//总行数
        ui->tableWidget->insertRow(rowcount);
        ui->tableWidget->setItem(rowcount,0,column);
        ui->tableWidget->setItem(rowcount,1,column1);
        ui->tableWidget->setItem(rowcount,2,column2);
        ui->tableWidget->setItem(rowcount,3,column3);
        ui->tableWidget->setItem(rowcount,4,column4);
        m_sum = m_sum+s2.toFloat()*s3.toInt();
        ui->lcdNumber->display(m_sum);
    }
    else
    {
        QMessageBox::warning(this,"提示","输入有误!");
    }

}

void Widget::on_pushButton_2_clicked() //删除
{
    int currow = ui->tableWidget->currentRow();//获取行号
    if(currow == -1)
    {
        QMessageBox::warning(this,"提示","操作有误!");
    }
    else
    {
        ui->tableWidget->removeRow(currow);//删除当前行
    }
}

void Widget::comeback()//信号槽,显示父窗口
{
    //判断该桌号是否点过餐
    if(FoodVec.begin() != FoodVec.end())
    {
        QString Table = FoodVec[1].table;
        ui->lineEdit->setText(Table);

        ui->lineEdit->setFocusPolicy(Qt::NoFocus);  //设置为只读模式
    }
    ui->tableWidget->setRowCount(0);
    m_sum = 0;
    this->show();
}

void Widget::Delete()//信号槽,退餐
{
    child->Delete_food();
}

childdorm.cpp

#include "childdorm.h"

#include "ui_childdorm.h"
childdorm::childdorm(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::childdorm)
{
    //获取父窗口变量
    //p = (Widget*) parent;  //获取父窗口指针

    ui->setupUi(this);
    this->setWindowTitle(QStringLiteral("点餐窗口"));
    //this->move(QPoint(100,100));
    this->setFixedSize(1500,800);//背景图尺寸
    this->setWindowIcon(QIcon(":/image/28.png"));//APP图标

    //设置为只读模式
    ui->tableWidget->setEditTriggers(QAbstractItemView::NoEditTriggers);
    ui->tableWidget_2->setEditTriggers(QAbstractItemView::NoEditTriggers);

    // 使表宽度自适应
    ui->tableWidget->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应
    ui->tableWidget_2->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应

    //居中显示
    QDesktopWidget* desktop = QApplication::desktop();
    move((desktop->width() - this->width())/2, (desktop->height() - this->height())/2);

    //add back picture
    QPalette pal = this->palette();//yunxu yong bi
   // pal.setBrush(QPalette::Background,QBrush(QPixmap(":/image/27.jpg")));//背景图
    setPalette(pal);

   //child = new Widget;
   //child->hide();

}

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

void childdorm::on_pushButton_3_clicked()//加餐
{
    this->hide();
    emit Interface();
}


void childdorm::getData(QWidget *parent) //获取父窗口指针
{
    //获取父窗口变量
    Widget * p = (Widget*) parent;  //获取父窗口指针
    FoodVec = p->getVec();
    FoodVec_No = p->getVecNo();
    tcpsocket = p->getsocket();
}


void childdorm::getvec(vector<FoodInfo> FoodVec_no,vector<FoodInfo> FoodVec_in)  //打印订单
{
    QStringList headtext;
    headtext<<"序号"<<"餐名"<<"价格"<<"数量"<<"备注";
    ui->tableWidget->setColumnCount(headtext.count());//列表设置为和headtext相等
    ui->tableWidget->setHorizontalHeaderLabels(headtext);//插入表头
    ui->tableWidget->setRowCount(0);
    ui->lineEdit->setText(FoodVec_no[1].table);

    for (int j=1;j<(FoodVec_no).size();j++)
    {
        int rowcount = ui->tableWidget->rowCount();

        ui->tableWidget->insertRow(rowcount);

        QTableWidgetItem *column = new QTableWidgetItem(FoodVec_no[j].number);
        QTableWidgetItem *column1 = new QTableWidgetItem(FoodVec_no[j].food);
        QTableWidgetItem *column2 = new QTableWidgetItem(FoodVec_no[j].price);
        QTableWidgetItem *column3 = new QTableWidgetItem(FoodVec_no[j].quatity);
        QTableWidgetItem *column4 = new QTableWidgetItem(FoodVec_no[j].post);

        ui->tableWidget->setItem(rowcount,0,column);
        ui->tableWidget->setItem(rowcount,1,column1);
        ui->tableWidget->setItem(rowcount,2,column2);
        ui->tableWidget->setItem(rowcount,3,column3);
        ui->tableWidget->setItem(rowcount,4,column4);

     }

    QStringList headtext1;
    headtext1<<"序号"<<"餐名"<<"价格"<<"数量"<<"备注";
    ui->tableWidget_2->setColumnCount(headtext1.count());//列表设置为和headtext相等
    ui->tableWidget_2->setHorizontalHeaderLabels(headtext1);//插入表头
    ui->tableWidget_2->setRowCount(0);

    for (int j=0;j<(FoodVec_in).size();j++)
    {
        int rowcount = ui->tableWidget_2->rowCount();

        ui->tableWidget_2->insertRow(rowcount);

        QTableWidgetItem *column = new QTableWidgetItem(FoodVec_in[j].number);
        QTableWidgetItem *column1 = new QTableWidgetItem(FoodVec_in[j].food);
        QTableWidgetItem *column2 = new QTableWidgetItem(FoodVec_in[j].price);
        QTableWidgetItem *column3 = new QTableWidgetItem(FoodVec_in[j].quatity);
        QTableWidgetItem *column4 = new QTableWidgetItem(FoodVec_in[j].post);

        ui->tableWidget_2->setItem(rowcount,0,column);
        ui->tableWidget_2->setItem(rowcount,1,column1);
        ui->tableWidget_2->setItem(rowcount,2,column2);
        ui->tableWidget_2->setItem(rowcount,3,column3);
        ui->tableWidget_2->setItem(rowcount,4,column4);

     }
}

void childdorm::Delete_food()  //退菜操作
{
        int currow = ui->tableWidget->currentRow();//获取行号
        if(currow == -1)
        {
            QMessageBox::warning(this,"提示","操作有误!");
        }
        else
        {
            QString str = ui->tableWidget->item(currow,0)->text(); //获取序号
            QString str1 = ui->tableWidget->item(currow,1)->text();//获取菜名
            QString str2 = ui->tableWidget->item(currow,2)->text();//获取价格
            QString str3 = ui->tableWidget->item(currow,3)->text();//获取价格
            QString str4 = ui->tableWidget->item(currow,4)->text();//获取备注

            QString S = ui->lineEdit->text(); //桌号
            QByteArray ba = S.toLocal8Bit();
            memcpy(F_head.table,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str.toLocal8Bit();
            memcpy(F_head.number,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str1.toLocal8Bit();
            memcpy(F_head.food,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str2.toLocal8Bit();
            memcpy(F_head.price,ba.data(),ba.size()+1);   //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str3.toLocal8Bit();
            memcpy(F_head.quatity,ba.data(),ba.size()+1); //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ba = str4.toLocal8Bit();
            memcpy(F_head.post,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
            ui->tableWidget->removeRow(currow);//删除当前行
        }

        for(int i = 0; i < FoodVec_No->size(); i++)
        {
            if((strcmp(FoodVec_No->at(i).number,F_head.number) == 0) && (strcmp(FoodVec_No->at(i).post,F_head.post) == 0))
            {
                FoodVec_No->erase(FoodVec_No->begin ()+i);//删除未上菜单中该元素
                break;
            }
        }

        for(int i = 0; i < FoodVec->size(); i++)
        {
            if((strcmp(FoodVec->at(i).number,F_head.number) == 0) && (strcmp(FoodVec->at(i).post,F_head.post) == 0))
            {
                FoodVec->erase(FoodVec->begin ()+i);//删除订单中该元素
                break;
            }
        }

        //向服务端发送订单信息
        QByteArray a1;
        a1.resize(sizeof(FoodInfo)*FoodVec->size());
        memcpy(a1.data(),FoodVec->data(),sizeof(FoodInfo)*FoodVec->size());
        tcpsocket->write(a1);
}

void childdorm::on_pushButton_clicked()//催餐
{
    QMessageBox::warning(this,"催餐","催餐成功!\n厨师正在努力中,请耐心等待!");
}

void childdorm::on_pushButton_2_clicked()//退餐
{
    emit Inter_delete();
}

2、收银端

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QSqlQuery>
#include <vector>
#include<QString>
#include<QTcpSocket>
#include "childdorm.h"
#include "structural.h"
using namespace std;

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

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

private slots:
    void on_pushButton_2_clicked();

    void on_pushButton_clicked();

    void comeback();//关闭此窗口
    void comeback_no();//登录失败
public:
    Ui::Widget *ui;
    FoodInfo F_head;//订单结构体
    vector<FoodInfo> foodVec;//通用订单容器
    vector<FoodInfo> FoodVec;//订单容器
    childdorm *child ;
};

#endif // WIDGET_H

childdorm.h

#ifndef CHILDDORM_H
#define CHILDDORM_H

#include <QWidget>
#include<QSqlQuery>
#include <vector>
#include<QString>
#include<QTcpSocket>
#include "structural.h"
using namespace std;

namespace Ui {
class childdorm;
}

class childdorm : public QWidget
{
    Q_OBJECT
signals:
    void Interface();//登录成功
    void Inter_no();//登录失败
public:
    explicit childdorm(QWidget *parent = 0);
    ~childdorm();
    void Init();    //初始化
    void client();  //客服端
    void flag(QByteArray array);          //标志位判断
    void log_in(QString name,QString pw); //发送登录信息
    void cashier_in();     //登录成功
    void cashier_no();     //登录失败
    void cashier_query();  //打印账单查询结果
    void cashier_refresh();//刷新餐桌状态
private slots:
    void on_pushButton_4_clicked();

    void on_pushButton_3_clicked();

    void on_pushButton_clicked();

    void on_pushButton_2_clicked();

    void on_pushButton_5_clicked();

private:
    Ui::childdorm *ui;
    QString m_name;  //用户名
    float m_sum;  //顾客消费总额
    QTcpSocket *tcpsocket;
    FoodInfo F_head;//订单结构体
    vector<FoodInfo> foodVec;//通用订单容器
    vector<FoodInfo> FoodVec;//订单容器

};

#endif // CHILDDORM_H

structrual.h

#ifndef STRUCTURAL_H
#define STRUCTURAL_H

typedef struct Food
{
    char table[5]; //桌号
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char quatity[10];//数量
    char post[200];//备注
}FoodInfo;

#endif // STRUCTURAL_H

main.cpp

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include "childdorm.h"//自己添加
#include <QDesktopWidget>
#include<QLabel>//自己添加
#include<QPalette>//自己添加
#include<QMessageBox>//对话框
#include<QFile>
Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->setWindowFlags(Qt::FramelessWindowHint);//去掉标题栏
    this->setFixedSize(400,377);//背景图尺寸
    this->move(QPoint(100,100));
    this->setWindowIcon(QIcon(":/image/5.png"));//APP图标

   //窗口居住显示
   QDesktopWidget* desktop = QApplication::desktop();
   move((desktop->width() - this->width())/2, (desktop->height() - this->height())/2);

    QPalette pal = this->palette();
    pal.setBrush(QPalette::Background,QBrush(QPixmap(":/image/1.jpg")));//背景图
    setPalette(pal);

    child = new childdorm();
    child->hide();
    //child->getData(this);   //通过this把父窗口的指针传到子窗口当中
    connect(child,SIGNAL(Interface()),this,SLOT(comeback()));  //信号槽
    connect(child,SIGNAL(Inter_no()),this,SLOT(comeback_no())); //信号槽
}

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

void Widget::on_pushButton_2_clicked()//退出
{
    exit(-1);
}

void Widget::on_pushButton_clicked()//登录
{
    QString name = ui->lineEdit->text();
    QString pw = ui->lineEdit_2->text();
    child->log_in(name,pw);  //发送登录信息
}

void Widget::comeback()//信号槽,关闭父窗口
{
    this->hide();
}

void Widget::comeback_no()//信号槽,登录失败
{
    QMessageBox::information(this,"登录失败!","用户名或密码错误!",QMessageBox::Yes,QMessageBox::Yes);
}

childdorm.cpp

#include "childdorm.h"
#include "ui_childdorm.h"
#include "widget.h"
#include <QDesktopWidget>
#include<QSqlQuery>
#include<QDebug>
#include<QString>
#include<cstring>
#include<QMessageBox>
#include<QSqlError>
#include<QHostAddress>
#include<QTableWidgetItem>
#include <QVariant>
#include<unistd.h>
using namespace std;
childdorm::childdorm(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::childdorm)
{
    ui->setupUi(this);
    this->setFixedSize(1500,800);//背景图尺寸
    // this->setWindowFlags(Qt::FramelessWindowHint);//去掉标题栏
    this->setWindowTitle(QStringLiteral("收银界面"));
    this->move(QPoint(100,100));
    this->setWindowIcon(QIcon(":/image/5.png"));//APP图标

    //窗口居住显示
    QDesktopWidget* desktop = QApplication::desktop();
    move((desktop->width() - this->width())/2, (desktop->height() - this->height())/2);

    QPalette pal = this->palette();
    //pal.setBrush(QPalette::Background,QBrush(QPixmap(":/image/27.jpg")));//背景图
    setPalette(pal);

    //ui->tableWidget->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应
    ui->tableWidget_2->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应

    Init();
    client();
}

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

void childdorm::Init()//初始化
{
    tcpsocket = new QTcpSocket(this);//创建客户端套接字


    connect(tcpsocket,&QTcpSocket::connected,//请求连接信号
           [=]()
    {
        //ui->textEdit->setText("成功连接服务器");
    }
    );

    QString ip = "192.168.12.13";
    qint16 port = 8888;
    tcpsocket->connectToHost(QHostAddress(ip),port);
}

void childdorm::client()        //客服端操作
{
    connect(tcpsocket,&QTcpSocket::readyRead,
            [=]()
    {
        QByteArray array = tcpsocket->readAll();
        flag(array);     //数据解析
    }
    );
}

void childdorm::flag(QByteArray array) //服务端信息判断
{
    FoodVec.clear(); //接收容器
    FoodVec.resize(array.size()/sizeof(FoodInfo));
    memcpy(FoodVec.data(),array.data(),array.size());
    qDebug()<<FoodVec[0].food;
    if(strcmp(FoodVec[0].food,"cashier_in")==0)//登录允许
    {
        cashier_in();
    }
    else if(strcmp(FoodVec[0].food,"cashier_no")==0)//登录失败
    {
        cashier_no();
    }
    else if(strcmp(FoodVec[0].food,"cashier_query")==0)//查询账单结果
    {
        cashier_query();
    }
    else if(strcmp(FoodVec[0].food,"cashier_refresh")==0)//刷新餐桌状态
    {
        cashier_refresh();
    }
}

void childdorm::log_in(QString name, QString pw)  //发送登录信息
{
    m_name = name;//记录用户名
    foodVec.clear();
    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"cashier");  //放入标志位
    strcpy(F_head.price,"\0");
    strcpy(F_head.quatity,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);//订单信息标志位放入容器中首元素

    QByteArray ba = name.toLocal8Bit();
    memcpy(F_head.food,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
    ba = pw.toLocal8Bit();
    memcpy(F_head.post,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
    foodVec.push_back(F_head);//放入登录信息

    QByteArray a1;
    a1.resize(sizeof(FoodInfo)*foodVec.size());
    memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
    tcpsocket->write(a1);
}

void childdorm::cashier_in()//允许登录
{
    emit Interface();
    ui->lineEdit_4->setText(m_name);
    ui->lineEdit_4->setFocusPolicy(Qt::NoFocus);  //设置为只读模式
    ui->lineEdit->setFocusPolicy(Qt::NoFocus);    //设置为只读模式
    ui->lineEdit_3->setFocusPolicy(Qt::NoFocus);  //设置为只读模式
    this->show();
}

void childdorm::cashier_no()//登录失败
{
     emit Inter_no();
}

void childdorm::cashier_query() //打印账单信息
{
    m_sum = 0;
    QStringList headtext;
    headtext<<"桌号"<<"序号"<<"餐名"<<"价格"<<"数量"<<"备注";
    ui->tableWidget->setColumnCount(headtext.count());//列表设置为和headtext相等
    ui->tableWidget->setHorizontalHeaderLabels(headtext);//插入表头
    ui->tableWidget->setRowCount(0);

    for (int j=1; j<FoodVec.size(); j++)
    {
        int rowcount = ui->tableWidget->rowCount();

        ui->tableWidget->insertRow(rowcount);

        QTableWidgetItem *column = new QTableWidgetItem(FoodVec[j].table);
        QTableWidgetItem *column1 = new QTableWidgetItem(FoodVec[j].number);
        QTableWidgetItem *column2 = new QTableWidgetItem(FoodVec[j].food);
        QTableWidgetItem *column3 = new QTableWidgetItem(FoodVec[j].price);
        QTableWidgetItem *column4 = new QTableWidgetItem(FoodVec[j].quatity);
        QTableWidgetItem *column5 = new QTableWidgetItem(FoodVec[j].post);

        ui->tableWidget->setItem(rowcount,0,column);
        ui->tableWidget->setItem(rowcount,1,column1);
        ui->tableWidget->setItem(rowcount,2,column2);
        ui->tableWidget->setItem(rowcount,3,column3);
        ui->tableWidget->setItem(rowcount,4,column4);
        ui->tableWidget->setItem(rowcount,5,column5);

        QString price = QString(FoodVec[j].price);
        QString quatity = QString(FoodVec[j].quatity);

        m_sum += (price.toFloat()) * (quatity.toInt());
        QString data = QString("%1").arg(m_sum);
        ui->lineEdit_3->setText(data);  //输出总消费额
     }
}

void childdorm::cashier_refresh() //刷新餐桌状态
{
    QStringList headtext;
    headtext<<"餐桌号"<<"使用状态";
    ui->tableWidget_2->setColumnCount(headtext.count());//列表设置为和headtext相等
    ui->tableWidget_2->setHorizontalHeaderLabels(headtext);//插入表头
    ui->tableWidget_2->setRowCount(0);

    for (int j=1; j<FoodVec.size(); j++)
    {
        int rowcount = ui->tableWidget_2->rowCount();

        ui->tableWidget_2->insertRow(rowcount);

        QTableWidgetItem *column = new QTableWidgetItem(FoodVec[j].table);
        QTableWidgetItem *column1 = new QTableWidgetItem(FoodVec[j].food);

        ui->tableWidget_2->setItem(rowcount,0,column);  //餐桌号
        ui->tableWidget_2->setItem(rowcount,1,column1); //使用状态
     }
}

void childdorm::on_pushButton_4_clicked()//重新登录
{
    this->hide();
    Widget *child = new Widget();
    child->show();
}

void childdorm::on_pushButton_3_clicked()//退出
{
    exit(-1);
}

void childdorm::on_pushButton_clicked()//查询
{
    QString S = ui->lineEdit_2->text(); //桌号
    ui->lineEdit->setText(S);
    char s[5];
    QByteArray ba = S.toLocal8Bit();
    memcpy(s,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

    if(S == "\0")
    {
        QMessageBox::warning(this,"提示!","请输入查询桌号!");
    }
    else
    {
        foodVec.clear();
        strcpy(F_head.table,s);
        strcpy(F_head.number,"\0");
        strcpy(F_head.food,"cashier_query");  //放入标志位:查询订单
        strcpy(F_head.price,"\0");
        strcpy(F_head.quatity,"\0");
        strcpy(F_head.post,"\0");
        foodVec.push_back(F_head);    //订单信息标志位放入容器中首元素

        QByteArray a1;
        a1.resize(sizeof(FoodInfo)*foodVec.size());
        memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
        tcpsocket->write(a1);
    }
}

void childdorm::on_pushButton_2_clicked()//结算
{
    QString S = ui->lineEdit->text(); //桌号
    char s[5];
    QByteArray ba = S.toLocal8Bit();
    memcpy(s,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

    QString Sum = ui->lineEdit_3->text(); //消费额
    char sum[5];
    ba = Sum.toLocal8Bit();
    memcpy(sum,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

    char name[100];
    ba = m_name.toLocal8Bit();
    memcpy(name,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止

    if(S == "\0")
    {
        QMessageBox::warning(this,"提示!","请先查询账单!");
    }
    else
    {
        foodVec.clear();
        strcpy(F_head.table,s);  //桌号
        strcpy(F_head.number,"\0");
        strcpy(F_head.food,"cashier_finish");  //放入标志位:结算
        strcpy(F_head.price,sum);  //消费额
        strcpy(F_head.quatity,"\0");
        strcpy(F_head.post,name);  //收银人
        foodVec.push_back(F_head);//订单信息标志位放入容器中首元素

        QByteArray a1;
        a1.resize(sizeof(FoodInfo)*foodVec.size());
        memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
        tcpsocket->write(a1);

        QMessageBox::warning(this,"提示!","结算成功!");
        //ui->tableWidget->clearContents();  //清空表中数据
        ui->tableWidget->setRowCount(0);   //清空表中数据
        ui->lineEdit->clear();             //清空表中数据
        ui->lineEdit_3->clear();           //清空表中数据
    }
}

void childdorm::on_pushButton_5_clicked()//刷新餐桌状态
{
    foodVec.clear();
    strcpy(F_head.table,"\0");  //桌号
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"cashier_refresh");  //放入标志位:刷新餐桌状态
    strcpy(F_head.price,"\0");  //消费额
    strcpy(F_head.quatity,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);  //订单信息标志位放入容器中首元素

    QByteArray a1;
    a1.resize(sizeof(FoodInfo)*foodVec.size());
    memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
    tcpsocket->write(a1);
}

3、厨房端

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QSqlQuery>
#include <vector>
#include<QString>
#include<QTcpSocket>
#include "structural.h"
using namespace std;
namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
    void Init();//初始化
    void client();//客服端
    void Order_print(QByteArray array);//打印订单
private slots:
    void on_pushButton_2_clicked();//退出

    void on_pushButton_clicked();//上菜

    void on_pushButton_3_clicked();//刷新

public:
    Ui::Widget *ui;
    //QSqlDatabase db;
    FoodInfo F_head;//订单结构体
    vector<FoodInfo> FoodVec;//订单容器
    vector<FoodInfo> foodVec;//通用容器
    QTcpSocket *tcpsocket;
};

#endif // WIDGET_H

structural.h

#ifndef STRUCTURAL_H
#define STRUCTURAL_H

typedef struct Food
{
    char table[5]; //桌号
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char quatity[10];//数量
    char post[200];//备注
}FoodInfo;

#endif // STRUCTURAL_H

main.cpp

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include <QDesktopWidget>
#include<QSqlQuery>
#include<QDebug>
#include<QString>
#include<cstring>
#include<QMessageBox>
#include<QSqlError>
#include<QHostAddress>
#include<QTcpSocket>
#include<QTableWidgetItem>
#include <QVariant>
using namespace std;
Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->setFixedSize(1500,800);//背景图尺寸
    this->setWindowTitle(QStringLiteral("厨房"));
   // this->move(QPoint(100,100));
    this->setWindowIcon(QIcon(":/image/3.png"));//APP图标

    //居中显示
    QDesktopWidget* desktop = QApplication::desktop();
    move((desktop->width() - this->width())/2, (desktop->height() - this->height())/2);

    //设置为只读模式
    ui->tableWidget->setEditTriggers(QAbstractItemView::NoEditTriggers);
    ui->tableWidget->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch); // 使表宽度自适应

    //add back picture
    QPalette pal = this->palette();//yunxu yong bi
    //pal.setBrush(QPalette::Background,QBrush(QPixmap(":/image/27.jpg")));//背景图
    setPalette(pal);

    Init();
    client();
}

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

void Widget::on_pushButton_2_clicked()
{
    exit(-1);
}

void Widget::Init()//初始化
{
    tcpsocket = new QTcpSocket;//创建客户端套接字


    connect(tcpsocket,&QTcpSocket::connected,//请求连接信号
           [=]()
    {
        //ui->textEdit->setText("成功连接服务器");
    }
    );

    QString ip = "192.168.12.13";
    qint16 port = 8888;
    tcpsocket->connectToHost(QHostAddress(ip),port);
}

void Widget::client()  //客服端操作
{
    foodVec.clear();
    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"chef");  //放入标志位
    strcpy(F_head.price,"\0");
    strcpy(F_head.quatity,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);//订单信息标志位放入容器中首元素
    QByteArray a1;
    a1.resize(sizeof(FoodInfo)*foodVec.size());
    memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
    tcpsocket->write(a1);


    connect(tcpsocket,&QTcpSocket::readyRead,
            [=]()
    {
        QByteArray array = tcpsocket->readAll();
        //qDebug()<< array;
        Order_print(array);     //订单打印
    }
    );
}

void Widget::Order_print(QByteArray array) //订单打印
{
    FoodVec.clear();
    FoodVec.resize(array.size()/sizeof(FoodInfo));
    memcpy(FoodVec.data(),array.data(),array.size());

    QStringList headtext;
    headtext<<"桌号"<<"序号"<<"餐名"<<"价格"<<"数量"<<"备注";
    ui->tableWidget->setColumnCount(headtext.count());     //列表设置为和headtext相等
    ui->tableWidget->setHorizontalHeaderLabels(headtext);  //插入表头
    ui->tableWidget->setRowCount(0);
    int rowcount;
    qDebug()<< FoodVec.size();
    //qDebug()<<FoodVec[7].food;
    for (int j=0;j< FoodVec.size();j++)
    {
        qDebug()<<FoodVec[j].food;
        rowcount = ui->tableWidget->rowCount();
        ui->tableWidget->insertRow(rowcount);
        QTableWidgetItem *column = new QTableWidgetItem(FoodVec[j].table);
        QTableWidgetItem *column1 = new QTableWidgetItem(FoodVec[j].number);
        QTableWidgetItem *column2 = new QTableWidgetItem(FoodVec[j].food);
        QTableWidgetItem *column3 = new QTableWidgetItem(FoodVec[j].price);
        QTableWidgetItem *column4 = new QTableWidgetItem(FoodVec[j].quatity);
        QTableWidgetItem *column5 = new QTableWidgetItem(FoodVec[j].post);

        ui->tableWidget->setItem(rowcount,0,column);
        ui->tableWidget->setItem(rowcount,1,column1);
        ui->tableWidget->setItem(rowcount,2,column2);
        ui->tableWidget->setItem(rowcount,3,column3);
        ui->tableWidget->setItem(rowcount,4,column4);
        ui->tableWidget->setItem(rowcount,5,column5);
    }

}

void Widget::on_pushButton_clicked()//上菜
{
    foodVec.clear();
    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"chef_in");  //放入标志位(厨房上菜)
    strcpy(F_head.price,"\0");
    strcpy(F_head.quatity,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);//订单信息标志位放入容器中首元素


    int currow = ui->tableWidget->currentRow();//获取行号
    if(currow == -1)
    {
        QMessageBox::warning(this,"提示","操作有误!");
    }
    else
    {
        QString str = ui->tableWidget->item(currow,0)->text(); //获取桌号
        QString str1 = ui->tableWidget->item(currow,1)->text();//获取序号
        QString str2 = ui->tableWidget->item(currow,2)->text();//获取菜名
        QString str3 = ui->tableWidget->item(currow,3)->text();//获取价格
        QString str4 = ui->tableWidget->item(currow,4)->text();//获取数量
        QString str5 = ui->tableWidget->item(currow,5)->text();//获取备注

        QByteArray ba = str.toLocal8Bit();
        memcpy(F_head.table,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        ba = str1.toLocal8Bit();
        memcpy(F_head.number,ba.data(),ba.size()+1);  //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        ba = str2.toLocal8Bit();
        memcpy(F_head.food,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        ba = str3.toLocal8Bit();
        memcpy(F_head.price,ba.data(),ba.size()+1);   //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        ba = str4.toLocal8Bit();
        memcpy(F_head.quatity,ba.data(),ba.size()+1); //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        ba = str5.toLocal8Bit();
        memcpy(F_head.post,ba.data(),ba.size()+1);    //加1是为了最后的终结符，否则转换回来的时候不知道什么时候截止
        foodVec.push_back(F_head);//菜品信息放入容器中

        ui->tableWidget->removeRow(currow);//删除当前行

        //发送所上菜品信息
        QByteArray a1;
        a1.resize(sizeof(FoodInfo)*foodVec.size());
        memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
        tcpsocket->write(a1);
    }


}

void Widget::on_pushButton_3_clicked()//刷新
{
    foodVec.clear();
    strcpy(F_head.table,"\0");
    strcpy(F_head.number,"\0");
    strcpy(F_head.food,"chef");  //放入标志位
    strcpy(F_head.price,"\0");
    strcpy(F_head.quatity,"\0");
    strcpy(F_head.post,"\0");
    foodVec.push_back(F_head);//订单信息标志位放入容器中首元素
    QByteArray a1;
    a1.resize(sizeof(FoodInfo)*foodVec.size());
    memcpy(a1.data(),foodVec.data(),sizeof(FoodInfo)*foodVec.size());
    tcpsocket->write(a1);
}

4、管理端

structural.h(结构体)

#ifndef STRUCTURAL_H
#define STRUCTURAL_H

typedef struct Food
{
    char table[5]; //桌号
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char quatity[10];//数量
    char post[200];//备注
}FoodInfo;

typedef struct Menu
{
    char number[10];//序号
    char food[100]; //餐名
    char price[10];//价格
    char state[20];//状态
}MenuInfo;

#endif // STRUCTURAL_H

widget.h（登录窗口）

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QSqlQuery>
#include<QSqlDatabase>
#include<QTcpServer>   //监听套接字的类
#include<QTcpSocket>   //建立套接字的类
#include "structural.h"
#include"mythread.h"
namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
    void tcp();
private slots:
    void on_pushButton_clicked();

    void on_pushButton_2_clicked();

private:
    Ui::Widget *ui;
    QSqlDatabase db;
    QTcpServer *tcpserver;
    QTcpSocket *tcpsocket;
};

#endif // WIDGET_H

childdorm.h(管理窗口)

#ifndef CHILDDORM_H
#define CHILDDORM_H

#include <QWidget>
#include<QTcpSocket>//建立套接字的类
#include<QTcpServer>//监听套接字的类
#include <vector>
#include<QSqlDatabase>
#include <QDesktopWidget>
#include<QSqlError>
#include<QLabel>//自己添加
#include<QPalette>//自己添加
#include<QMessageBox>//对话框

#include "structural.h"
#include "widget.h"
#include "add_users.h"
#include "change_per.h"
#include "change_pw.h"
#include "add_food.h"
#include "change_price.h"
#include "change_status.h"
#include "add_drinks.h"
#include "modify_drinks.h"
#include "modify_stutus.h"
#include "bill.h"
#include <QDesktopWidget>
using namespace std;

namespace Ui {
class childdorm;
}

class childdorm : public QWidget
{
    Q_OBJECT

public:
    explicit childdorm(QWidget *parent = 0);
    ~childdorm();
    void Menu_frint();//打印菜单
    void User_frint();//打印用户
    void Bill_frint();//打印账单
    void Init();      //初始化
    void getname(QString name);//打印管理者姓名
private slots:
    void on_pushButton_2_clicked();

    void on_pushButton_clicked();

    void on_pushButton_3_clicked();

    void on_pushButton_5_clicked();

    void on_pushButton_6_clicked();

    void on_pushButton_8_clicked();

    void on_pushButton_10_clicked();

    void on_pushButton_11_clicked();

    void on_pushButton_13_clicked();

    void on_pushButton_15_clicked();

    void on_pushButton_16_clicked();

    void on_pushButton_18_clicked();

    void on_pushButton_7_clicked();

    void on_pushButton_19_clicked();

    void on_pushButton_17_clicked();

    void on_pushButton_12_clicked();

    void on_pushButton_4_clicked();

    void on_pushButton_9_clicked();

    void on_pushButton_14_clicked();

private:
    Ui::childdorm *ui;
    QTcpServer *Server;
    QTcpSocket *Socket;
    QSqlDatabase db;
    vector<MenuInfo> MenuVec;//菜单容器
    MenuInfo M_head;//菜单结构体
    vector<FoodInfo> Foodvec;//订单容器
    FoodInfo F_head;//订单结构体
};

#endif // CHILDDORM_H

add_drinks.h(添加饮品)

#ifndef ADD_DRINKS_H
#define ADD_DRINKS_H

#include <QWidget>
#include<QSqlQuery>
#include<QSqlDatabase>
#include<QLabel>//自己添加
#include<QPalette>//自己添加
#include<QMessageBox>//对话框
#include<QSqlError>
#include <QDesktopWidget>
namespace Ui {
class Add_drinks;
}

class Add_drinks : public QWidget
{
    Q_OBJECT

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

private slots:
    void on_pushButton_clicked();

    void on_pushButton_2_clicked();

private:
    Ui::Add_drinks *ui;
    QSqlDatabase db;
};

#endif // ADD_DRINKS_H

add_food.h(添加菜品)

#ifndef ADD_FOOD_H
#define ADD_FOOD_H

#include <QWidget>
#include<QSqlQuery>
#include<QSqlDatabase>
#include<QLabel>//自己添加
#include<QPalette>//自己添加
#include<QMessageBox>//对话框
#include<QSqlError>
#include <QDesktopWidget>
namespace Ui {
class Add_food;
}

class Add_food : public QWidget
{
    Q_OBJECT

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

private slots:
    void on_pushButton_2_clicked();

    void on_pushButton_clicked();

private:
    Ui::Add_food *ui;
    QSqlDatabase db;
};

#endif // ADD_FOOD_H