基于QT5实现简易计算器

我不是女神ヾ 2023-01-12 13:58 213阅读 0赞

### 基于QT5实现简易计算器 ###

*  一、写在前面
 *  二、成品展示
 *  三、界面布局
 *  四、按钮功能
 *  五、源码下载
 *  六、补充

--------------------

# 一、写在前面 #

软件介绍：

> 仿照win10计算器，基于qt5实现具有简单运算的计算器。

环境：

> QT 5.12.2+QT Creator 4.8.2+win10

# 二、成品展示 #

按照惯例，直接上图  
在按钮上鼠标悬停与按下有不同颜色  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70]

# 三、界面布局 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 1]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 2]

可以看到我使用的是一个网格布局GridLayout和四个垂直布局VerticalLayout，每个垂直布局对应的是一列按钮。先把VerticalLayout拖出来放到界面空白处，再把按钮拖进去，最后把VerticalLayout拖进GridLayout即可。直接用网格布局应该也是可以的，建议大家尝试一下。  
控件的名称我写的比较随意，建议大家对照下图进行布局：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 3]

为了使按钮能够填满布局，按住CTRL并逐一点击所有按钮将其选中，在右侧属性面板中，将sizepolicy改为下图所示。  
![在这里插入图片描述][20210128163514222.png]

接着设置按钮字体，**选中所有数字按钮0-9**，更改字体为：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 4]  
**选中其他按钮**，更改字体为：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 5]  
**选中显示结果的LineEdit**，右键选择改变样式表，将字体改为黑色。

color: rgb(0, 0, 0);

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 6]  
最后，在.cpp文件的构造函数中的 ui->setupUi(this); 之后，加入如下代码：

ui->pushButton_1->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_2->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_3->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_4->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_5->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_6->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_7->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_8->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_9->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_0->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_zf->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_poi->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_equ->setStyleSheet(
                        "QPushButton{background-color:rgb(163,163,163);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(113,113,113);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(63,63,63);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_bfh->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_CE->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_C->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_bac->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_fs->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_pf->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_kg->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_div->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_mul->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_sub->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_add->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
    
    
    	//靠右垂直居中显示
        ui->lineEdit->setText("0");        //初始化
        ui->lineEdit->setAlignment( Qt::AlignHCenter);
        ui->lineEdit->setAlignment(Qt::AlignRight);

通过代码设置样式表，来设置按钮正常显示、鼠标悬停、按下三种状态下的颜色，以及LineEdit的数字靠右垂直居中显示。这一大段有不少重复，其实可以直接选中相同颜色的多个按钮，直接右键改变样式表即可。

# 四、按钮功能 #

直接把代码贴出来吧，注意这里的槽函数需要在ui中按钮右键转到槽自动生成槽函数，另外控件的名称要对应好。  
![在这里插入图片描述][20210128165248236.png]  
**caculator.h**

#ifndef CACULATOR_H
    #define CACULATOR_H
    
    #include <QMainWindow>
    
    namespace Ui { 
    class caculator;
    }
    
    class caculator : public QMainWindow
    { 
        Q_OBJECT
    
    public:
        explicit caculator(QWidget *parent = 0);
        ~caculator();
        int m_var2;
        int m_var3;
        int m_var1;
        double display;
        bool iscontinue;
        bool isstr;
        QString str;
        double result;
        double num1;
        double num2;
        int count;
        bool isdot;
        bool  Dot;
        int isDel;
        double buttonDownNum(int numSize);
    
    private slots:
        void on_pushButton_1_clicked();
    
        void on_pushButton_2_clicked();
    
        void on_pushButton_3_clicked();
    
        void on_pushButton_4_clicked();
    
        void on_pushButton_5_clicked();
    
        void on_pushButton_6_clicked();
    
        void on_pushButton_7_clicked();
    
        void on_pushButton_8_clicked();
    
        void on_pushButton_9_clicked();
    
        void on_pushButton_add_clicked();
    
        void on_pushButton_sub_clicked();
    
        void on_pushButton_mul_clicked();
    
        void on_pushButton_div_clicked();
    
        void on_pushButton_equ_clicked();
    
        void on_pushButton_zf_clicked();
    
        void on_pushButton_0_clicked();
    
        void on_pushButton_poi_clicked();
    
        void on_pushButton_fs_clicked();
    
        void on_pushButton_pf_clicked();
    
        void on_pushButton_kg_clicked();
    
        void on_pushButton_bfh_clicked();
    
        void on_pushButton_CE_clicked();
    
        void on_pushButton_C_clicked();
    
        void on_pushButton_bac_clicked();
    
    private:
        Ui::caculator *ui;
    };
    
    #endif // CACULATOR_H

**caculator.cpp**

#include "caculator.h"
    #include "ui_caculator.h"
    #include "QVBoxLayout"
    #include "QGridLayout"
    #include "QtMath"
    
    
    caculator::caculator(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::caculator)
      ,m_var2(0),m_var3(0),m_var1(0),display(0)
    { 
        ui->setupUi(this);
        display = 0.0;
        num1 = 0;
        num2 = 0;
        result = 0.0;
        str = "";
        isstr = false;
        iscontinue = false;
        Dot = false;
        count = 1;
        isDel = 0;
        ui->pushButton_1->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_2->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_3->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_4->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_5->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_6->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_7->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_8->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_9->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_0->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_zf->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_poi->setStyleSheet(
                        "QPushButton{background-color:rgb(250,250,250);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_equ->setStyleSheet(
                        "QPushButton{background-color:rgb(163,163,163);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(113,113,113);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(63,63,63);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_bfh->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_CE->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_C->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_bac->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_fs->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_pf->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_kg->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_div->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_mul->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_sub->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
        ui->pushButton_add->setStyleSheet(
                        "QPushButton{background-color:rgb(240,240,240);border: 0px;}"
                        "QPushButton:hover{background-color: rgb(209,209,209);border:none;color:rgb(255, 255, 255);color:black}"
                        "QPushButton:pressed{background-color: rgb(187,187,187);border:none;color:rgb(255, 255, 255);color:black}"
                    );
    
    
    
        ui->lineEdit->setText("0");        //初始化
        ui->lineEdit->setAlignment( Qt::AlignHCenter);
        ui->lineEdit->setAlignment(Qt::AlignRight);
    
    }
    
    caculator::~caculator()
    { 
        delete ui;
    }
    
    double caculator::buttonDownNum(int numSize)
    { 
        if (!isstr) //运算符没有被按下，那就是num1
        { 
            if (!iscontinue) //按下一次
            { 
                num1 = numSize;
                iscontinue = true;
            }
            else
            { 
                if(isDel>0){ 
                        count=count-isDel;
                        isDel = 0;;
                    }
                num1 = num1 * pow(10, count) + numSize;
                if (Dot)
                { 
    
                    num1 = num1 / (pow(10, count));
                    count++;
    
                }
            }
    
            return num1;
        }
        else  //有运算符被按下
        { 
            if (!iscontinue) //是否连续按下
            { 
                num2 = numSize;
                iscontinue = true;
            }
            else
            { 
                num2 = num2 * pow(10, count) + numSize;
                if (Dot)
                { 
                    num2 = num2 / (pow(10, count));
                    count++;
                }
            }
    
            return num2;
        }
    }
    
    
    
    
    
    void caculator::on_pushButton_1_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(1)));
    }
    
    void caculator::on_pushButton_2_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(2)));
    }
    
    void caculator::on_pushButton_3_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(3)));
    }
    
    void caculator::on_pushButton_4_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(4)));
    }
    
    void caculator::on_pushButton_5_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(5)));
    }
    
    void caculator::on_pushButton_6_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(6)));
    }
    
    void caculator::on_pushButton_7_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(7)));
    }
    
    void caculator::on_pushButton_8_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(8)));
    }
    
    void caculator::on_pushButton_9_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(9)));
    }
    
    void caculator::on_pushButton_0_clicked()
    { 
        ui->lineEdit->setText(QString::number(buttonDownNum(0)));
    }
    
    void caculator::on_pushButton_add_clicked()
    { 
        str = "+";
        isstr = true;
        iscontinue = false;
        Dot = false;
        count = 1;
    }
    
    void caculator::on_pushButton_sub_clicked()
    { 
        str = "-";
        isstr = true;
        iscontinue = false;
        Dot = false;
        count = 1;
    }
    
    void caculator::on_pushButton_mul_clicked()
    { 
        str = "*";
        isstr = true;
        iscontinue = false;
        Dot = false;
        count = 1;
    }
    
    void caculator::on_pushButton_div_clicked()
    { 
        str = "/";
        isstr = true;
        iscontinue = false;
        Dot = false;
        count = 1;
    }
    
    void caculator::on_pushButton_equ_clicked()
    { 
        if (str == "+")
            result = num1 + num2;
        else if (str == "-")
            result = num1 - num2;
        else if (str == "*")
            result = num1 * num2;
        else if (str == "/")
        { 
            result = double(num1) / double(num2);
        }
        num1 = result;
        display = result;
        isstr = false;
        iscontinue = false;
        Dot = false;
        count = 1;
        ui->lineEdit->setText(QString::number(display));
    }
    
    void caculator::on_pushButton_zf_clicked()
    { 
        result = -num1;
        num1 = result;
        display = result;
        isstr = false;
        iscontinue = false;
        Dot = false;
        count = 1;
        ui->lineEdit->setText(QString::number(display));
    }
    
    
    
    void caculator::on_pushButton_poi_clicked()
    { 
        Dot = true;
    }
    
    void caculator::on_pushButton_fs_clicked()
    { 
        result = 1 / num1;
            num1 = result;
            display = result;
            isstr = false;
            iscontinue = false;
            Dot = false;
            count = 1;
            ui->lineEdit->setText(QString::number(display));
    }
    
    void caculator::on_pushButton_pf_clicked()
    { 
    
        result = num1*num1;
            num1 = result;
            display = result;
            isstr = false;
            iscontinue = false;
            Dot = false;
            count = 1;
            ui->lineEdit->setText(QString::number(display));
    }
    
    void caculator::on_pushButton_kg_clicked()
    { 
        result = sqrt(num1);
        num1 = result;
        display = result;
        isstr = false;
        iscontinue = false;
        Dot = false;
        count = 1;
        ui->lineEdit->setText(QString::number(display));
    }
    
    void caculator::on_pushButton_bfh_clicked()
    { 
    
    }
    
    void caculator::on_pushButton_CE_clicked()
    { 
        if(iscontinue)
        { 
            num2=0;
        }
        else
        { 
            num1=0;
        }
        count = 1;
        isDel = 0;
        Dot=false;
        ui->lineEdit->setText(QString::number(0));
    }
    
    void caculator::on_pushButton_C_clicked()
    { 
        num1 = 0;
        num2 = 0;
        display = 0;
        iscontinue = false;
        isstr = false;
        Dot = false;
        count = 1;
        isDel = 0;
        ui->lineEdit->setText(QString::number(display));
    }
    
    int num(double f)
    { 
        int i = 0;
        while (i++, f != (int)f)
            f *= 10;
        return i - 1;
    }
    
    void caculator::on_pushButton_bac_clicked()
    { 
        isDel ++;
            if (isDel > count)
                isDel = count;
            if (!isstr) { 
                if (num1 - (int)num1 > 0){ 
                    int weishu = num(num1);
                    num1 = num1 * pow(10,weishu);
                    num1 = (int)num1 / 10;
                    num1 = num1 / pow(10, weishu - 1);
                    display = num1;
                    ui->lineEdit->setText(QString::number(display));
                }else{ 
                        num1 = (int)num1 / 10;
                        display = num1;
                        ui->lineEdit->setText(QString::number(display));
                }
            }
            else { 
                if (num2 - (int)num2 > 0) { 
                    int weishu = num(num2);
                    num2 = num2 * pow(10, weishu);
                    num2 = (int)num2 / 10;
                    num2 = num2 / pow(10, weishu - 1);
                    display = num2;
                    ui->lineEdit->setText(QString::number(display));
                }
                else { 
                    num2 = (int)num2 / 10;
                    display = num2;
                    ui->lineEdit->setText(QString::number(display));
                }
            }
    }

**main.cpp**

#include "caculator.h"
    #include <QApplication>
    
    int main(int argc, char *argv[])
    { 
        QApplication a(argc, argv);
        caculator w;
        w.setStyleSheet("background-color:rgb(230,230,230);");
        w.setWindowTitle("计算器");
        w.show();
    
        return a.exec();
    }

# 五、源码下载 #

完整源码已上传至CSDN，[点我下载][Link 1]。

# 六、补充 #

*  如果有一些找不到函数的错误，可能是函数名与我不一样或是界面ui名称和我不一样，这个需要自己注意一下哦
 *  有一些按钮的功能没有实现，在运算逻辑上也有一些bug
 *  有什么问题的话可以在评论区提出来，我会第一时间回复

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70]: /images/20221119/0ae34e1b1c1a48bf9b64acda0f867c4a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 1]: /images/20221119/6b2f96b5734f43f499b2a7e571f95f3c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 2]: /images/20221119/621dbe0bd76149279114fde6e5c6918e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 3]: /images/20221119/2be5909e2cfc4cecae2752d756af047a.png
[20210128163514222.png]: /images/20221119/ccf61a93c33a4021bfb5d669440a4315.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 4]: /images/20221119/40c2beaf82c3484787a633afa49603dc.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 5]: /images/20221119/3709e84fea1e4ae18730017dd8505492.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNzA2OTY5_size_16_color_FFFFFF_t_70 6]: /images/20221119/67a159fe01e74b4099fe230de2550edb.png
[20210128165248236.png]: /images/20221119/0772e8790f8647739c2ac1e011cf3276.png
[Link 1]: https://download.csdn.net/download/qq_43706969/14950516