简单工厂模式的练习==商场收银

拼搏现实的明天。 2022-07-16 17:56 48阅读 0赞

看了简单工厂模式后，心里总是痒痒的，想要做个小东西来练习一下，看到书上是以c\#做了一个简单的商场收银小系统为例子，于是，我便用qt和c++把这个小系统改写了一遍，也算是把这个简单工厂模式练习了一下。

![SouthEast][]![SouthEast 1][]

以下是代码：

#ifndef WIDGET_H
    #define WIDGET_H
    
    #include <QWidget>
    
    namespace Ui {
    class Widget;
    }
    
    class Widget : public QWidget
    {
        Q_OBJECT
        
    public:
        explicit Widget(QWidget *parent = 0);
        ~Widget();
        
    private slots:
        void on_pushButton_clicked();
    
        void on_pushButton_2_clicked();
    
    private:
        Ui::Widget *ui;
        double totalprice;
        double firstmoney;
        double price;
        int    num;
        QString record;
        double oldmoney;
        double returnmonry;
    };
    
    #endif // WIDGET_H

#include "widget.h"
    #include "ui_widget.h"
    #include <QDebug>
    
    class Cash                                                          //收费基类
    {
    public:
        virtual void setdis(double dis){ return; }                      //打折 折扣赋值虚函数
        virtual void setmoney(double oldmon, double retmon){ return; }  //满减 返利赋值虚函数
        virtual double acceptcash(double money)                         //总计算法虚函数
        {
            return money;
        }
    };
    
    class Normal : public Cash                                          //正常收费
    {
    public:
        double acceptcash(double money)                                 //正常收费算法
        {
            return money;
        }
    };
    
    class Discount : public Cash                                        //打折收费
    {
        double m_dis;                                                   //折扣
    public:
        void setdis(double dis)                                         //折扣赋值
        {
            m_dis = dis;
        }
        double acceptcash(double money)                                 //打折算法收费
        {
            return money * m_dis;
        }
    };
    
    class Returnmoney : public Cash                                     //满减收费  例满300减50
    {
        double oldmoney;                                                //满的值    此值为300
        double returnmoney;                                             //返的值    此值为50
    public:
        void setmoney(double oldmon, double retmon)                     //两个值赋值
        {
            oldmoney = oldmon;
            returnmoney = retmon;
        }
        double acceptcash(double money)                                 //满减算法
        {
            money = money - money * returnmoney / oldmoney;
            return money;
        }
    };
    
    class CashFoctory                                                   //收费算法 工厂类
    {
        Cash *cash;
    public:
        Cash* cashcreate(double sec)
        {
            if(sec == 1.0)                                              //正常收费
            {
                cash = new Normal;
            }
            else if(sec == 2.0)                                         //满减收费
            {
                cash = new Returnmoney;
            }
            else                                                        //打折收费
            {
                cash = new Discount;
                cash->setdis(sec);
            }
            return cash;
        }
    };
    
    double my_discount(QString dis)
    {
        if(dis == "正常收费")
        {
            return 1.0;
        }
        if(dis == "打9折")
        {
            return 0.9;
        }
        if(dis == "打8折")
        {
            return 0.8;
        }
        if(dis == "打7折")
        {
            return 0.7;
        }
        if(dis == "打6折")
        {
            return 0.6;
        }
        if(dis == "打5折")
        {
            return 0.5;
        }
        if(dis == "打4折")
        {
            return 0.4;
        }
        if(dis == "打3折")
        {
            return 0.3;
        }
        if(dis == "打2折")
        {
            return 0.2;
        }
        if(dis == "打1折")
        {
            return 0.1;
        }
    }
    
    Widget::Widget(QWidget *parent) :
        QWidget(parent),
        ui(new Ui::Widget)
    {
        ui->setupUi(this);
    }
    
    Widget::~Widget()
    {
        delete ui;
    }
    
    void Widget::on_pushButton_clicked()                                    //重置按钮槽函数
    {
        ui->priceedit->clear();
        ui->numedit->clear();
    }
    
    void Widget::on_pushButton_2_clicked()                                  //确定按钮槽函数
    {
        price = ui->priceedit->text().toDouble();                           //获取单价
        num = ui->numedit->text().toInt();                                  //获取数量
        QString dis;
        dis = ui->discountbox->currentText();                               //获取折扣
        double Dis;
        Dis = my_discount(dis);                                             //将对应的复选框中的文字转化为折扣
    
        if((ui->oldmoney->text() != "") && (ui->returnmoney->text() != "")) //满减有值的时候
        {
            oldmoney = ui->oldmoney->text().toDouble();
            returnmonry = ui->returnmoney->text().toDouble();
            Dis = 2.0;
        }
    
        CashFoctory F;                                                      //定义工厂类实例
        Cash* cash;
        cash = F.cashcreate(Dis);
        cash->setmoney(oldmoney, returnmonry);
    
        firstmoney = price * num;
        totalprice = totalprice + cash->acceptcash(firstmoney);             //计算合计
    
        QFont ft;
        ft.setPointSize(32);
        ft.setBold(true);
        ui->totalprice->setFont(ft);
        ui->totalprice->setText(tr("%1").arg(totalprice));
        record = record + QString("单价:%1 元   数量: %2 个   合计:%3  元\n").arg(price).arg(num).arg(totalprice);
        ui->textBrowser->setText(record);
    }

#include <QtGui/QApplication>
    #include "widget.h"
    #include <QTextCodec>
    
    int main(int argc, char *argv[])
    {
        QApplication a(argc, argv);
        QTextCodec::setCodecForTr(QTextCodec::codecForLocale());
        QTextCodec::setCodecForCStrings(QTextCodec::codecForLocale());
        Widget w;
        w.show();
        
        return a.exec();
    }

[SouthEast]: https://img-blog.csdn.net/20170304162319453?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvaGpmMTYxMTA1/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast
[SouthEast 1]: /images/20220709/ca3c7bc0e523415f965e8400c28a79aa.png