C++QT # 仿windows计算器

calculator.h

#ifndef CALCULATOR_H
#define CALCULATOR_H

#include <QMainWindow>


namespace Ui {
class Calculator;
}

class Calculator : public QMainWindow
{
    Q_OBJECT

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

private slots:
    void on_btn0_clicked();
    void on_btn1_clicked();
    void on_btn2_clicked();
    void on_btn3_clicked();
    void on_btn4_clicked();
    void on_btn5_clicked();
    void on_btn6_clicked();
    void on_btn7_clicked();
    void on_btn8_clicked();
    void on_btn9_clicked();
    void on_btnAdd_clicked();
    void on_btnSub_clicked();
    void on_btnMul_clicked();
    void on_btnDiv_clicked();
    void on_btnSign_clicked();
    void on_btnC_clicked();
    void on_btnCE_clicked();
    void on_btnDel_clicked();
    void on_btnSqrt_clicked();
    void on_btnPercent_clicked();
    void on_btnRooting_clicked();
    void on_btnMC_clicked();
    void on_btnMR_clicked();
    void on_btnMS_clicked();
    void on_btnMAdd_clicked();
    void on_btnMSub_clicked();
    void on_btnEqual_clicked();
    void on_btnPoint_clicked();

private:
    Ui::Calculator *ui;
    double current,past,memory;
    int cntDecDig;
    char sign;
};

#endif // CALCULATOR_H

calculator.cpp

#include "calculator.h"
#include "ui_calculator.h"
#include <cmath>
Calculator::Calculator(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::Calculator)
{
    ui->setupUi(this);
    //初始化
    sign = 0;
    memory = 0;
    past = current = cntDecDig = 0;
    //禁止调整窗口大小
    setWindowFlags(windowFlags()& ~Qt::WindowMaximizeButtonHint);
    setFixedSize(this->width(),this->height());
    //修改按钮样式
    setStyleSheet("QPushButton{background-color:#F0FFFF;color:black;}");
}

Calculator::~Calculator()
{
    delete ui;
}
//数字0
void Calculator::on_btn0_clicked()
{
    if(cntDecDig>0){//小数
        cntDecDig++;
    }else{//整数
        current = current*10;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字1
void Calculator::on_btn1_clicked()
{
    if(cntDecDig>0){//小数
        current += 1*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+1;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字2
void Calculator::on_btn2_clicked()
{
    if(cntDecDig>0){//小数
        current += 2*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+2;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字3
void Calculator::on_btn3_clicked()
{
    if(cntDecDig>0){//小数
        current += 3*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+3;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字4
void Calculator::on_btn4_clicked()
{
    if(cntDecDig>0){//小数
        current += 4*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+4;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字5
void Calculator::on_btn5_clicked()
{
    if(cntDecDig>0){//小数
        current += 5*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+5;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字6
void Calculator::on_btn6_clicked()
{
    if(cntDecDig>0){//小数
        current += 6*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+6;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字7
void Calculator::on_btn7_clicked()
{
    if(cntDecDig>0){//小数
        current += 7*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+7;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字8
void Calculator::on_btn8_clicked()
{
    if(cntDecDig>0){//小数
        current += 8*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+8;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//数字9
void Calculator::on_btn9_clicked()
{
    if(cntDecDig>0){//小数
        current += 9*pow(10,-cntDecDig);
        cntDecDig++;
    }else{//整数
        current = current*10+9;
    }
    ui->down->setText(QString::number(current,'f',10));
}
//加法
void Calculator::on_btnAdd_clicked()
{
    if(sign!=0){
        sign = '+';
        return;
    }
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current = 0;
    cntDecDig = 0;
    sign = '+';
    ui->down->setText(QString::number(current,'f',10));
}
//减法
void Calculator::on_btnSub_clicked()
{
    if(sign!=0){
        sign = '-';
        return;
    }
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current = 0;
    cntDecDig = 0;
    sign = '-';
    ui->down->setText(QString::number(current,'f',10));
}
//乘法
void Calculator::on_btnMul_clicked()
{
    if(sign!=0){
        sign = '*';
        return;
    }
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current = 0;
    cntDecDig = 0;
    sign = '*';
    ui->down->setText(QString::number(current,'f',10));
}
// 除法
void Calculator::on_btnDiv_clicked()
{
    if(sign!=0){
        sign = '/';
        return;
    }
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current = 0;
    cntDecDig = 0;
    sign = '/';
    ui->down->setText(QString::number(current,'f',10));
}
//点击± 符号变号
void Calculator::on_btnSign_clicked()
{
    current = -current;
    ui->down->setText(QString::number(current,'f',10));
}
//归零 清除当前的计算
void Calculator::on_btnC_clicked()
{
    ui->up->setText("0.0000000000");
    current = 0;
    sign = 0;
    cntDecDig = 0;
    ui->down->setText(QString::number(current,'f',10));
}
//清除显示的数字
void Calculator::on_btnCE_clicked()
{
    current = 0;
    cntDecDig = 0;
    ui->down->setText("0.0000000000");
}
//删除最后一位数字
void Calculator::on_btnDel_clicked()
{
    QString s = QString::number(current);
    s = s.left(s.size()-1);
    current = s.toDouble();
    ui->down->setText(QString::number(current,'f',10));
}
//平方根
void Calculator::on_btnSqrt_clicked()
{
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current = sqrt(current);
    ui->down->setText(QString::number(current,'f',10));
    current = 0;
}
//显示某个数的百分比
void Calculator::on_btnPercent_clicked()
{
    QString s = QString::number(current);
    current = s.toDouble();
    cntDecDig -= 2;
    if(cntDecDig<0)cntDecDig = 0;
    ui->down->setText(QString::number(current*100,'f',10)+"%");
}
//n次方根
void Calculator::on_btnRooting_clicked()
{
    if(sign!=0){
        sign = 'R';
        return;
    }
    ui->up->setText(QString::number(current,'f',10));
    sign = 'R';
    past = current;
    current = 0;
    ui->down->setText(QString::number(current,'f',10));
}
//清除存储器中的数值
void Calculator::on_btnMC_clicked()
{
    memory = 0;
}
//将存于存储器中的数显示在计算器的显示框上
void Calculator::on_btnMR_clicked()
{
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    ui->down->setText(QString::number(current,'f',10));
    current = 0;
}
//将显示框的数值存于存储器中
void Calculator::on_btnMS_clicked()
{
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    memory = current;
    cntDecDig = 0;
    current = 0;
}
//将显示框的数与存储器中的数相加并进行存储
void Calculator::on_btnMAdd_clicked()
{
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current += memory;
    ui->down->setText(QString::number(current,'f',10));
}
//将显示框的数与存储器中的数相减并进行存储
void Calculator::on_btnMSub_clicked()
{
    ui->up->setText(QString::number(current,'f',10));
    past = current;
    current -= memory;
    ui->down->setText(QString::number(current,'f',10));
    current = 0;
}
//计算最终结果
void Calculator::on_btnEqual_clicked()
{
    if(sign==0){
        ui->up->setText(QString::number(current,'f',10));
        past = current;
    }else{
        double tmp = past;
        past = current;
        switch(sign){
        case '+':
            current = tmp + past;
            break;
        case '-':
            current = tmp - past;
            break;
        case '*':
            current = tmp * past;
            break;
        case '/':
            if(past == 0)break;
            current = tmp / past;
            break;
        case 'R'://n次根号
            current = pow(tmp,(double)1.0/past);
            break;
        }
        ui->up->setText(QString::number(past,'f',10));
        ui->down->setText(QString::number(current,'f',10));
        sign = 0;
        cntDecDig = 0;
        past = current;
        current = 0;
    }
}

void Calculator::on_btnPoint_clicked()
{
    if(cntDecDig==0)cntDecDig++;
}

main.cpp

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

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

    return a.exec();
}

calculator.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Calculator</class>
 <widget class="QMainWindow" name="Calculator">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>369</width>
    <height>436</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Calculator</string>
  </property>
  <widget class="QWidget" name="centralWidget">
   <widget class="QWidget" name="layoutWidget">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>0</y>
      <width>497</width>
      <height>391</height>
     </rect>
    </property>
    <layout class="QGridLayout" name="gridLayout_2">
     <item row="1" column="0">
      <widget class="QLineEdit" name="down">
       <property name="text">
        <string>0.0000000000</string>
       </property>
       <property name="alignment">
        <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
       </property>
       <property name="readOnly">
        <bool>true</bool>
       </property>
      </widget>
     </item>
     <item row="0" column="0">
      <widget class="QLineEdit" name="up">
       <property name="alignment">
        <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
       </property>
       <property name="readOnly">
        <bool>true</bool>
       </property>
      </widget>
     </item>
     <item row="5" column="0">
      <layout class="QHBoxLayout" name="horizontalLayout_4">
       <item>
        <widget class="QPushButton" name="btn4">
         <property name="text">
          <string>4</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btn5">
         <property name="text">
          <string>5</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btn6">
         <property name="text">
          <string>6</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnMul">
         <property name="text">
          <string>*</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnRooting">
         <property name="text">
          <string>1/x</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
      </layout>
     </item>
     <item row="2" column="0">
      <layout class="QHBoxLayout" name="horizontalLayout">
       <item>
        <widget class="QPushButton" name="btnMC">
         <property name="text">
          <string>MC</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnMR">
         <property name="text">
          <string>MR</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnMS">
         <property name="text">
          <string>MS</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnMAdd">
         <property name="text">
          <string>M+</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnMSub">
         <property name="text">
          <string>M-</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
      </layout>
     </item>
     <item row="3" column="0">
      <layout class="QHBoxLayout" name="horizontalLayout_2">
       <item>
        <widget class="QPushButton" name="btnDel">
         <property name="text">
          <string>←</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnCE">
         <property name="text">
          <string>CE</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnC">
         <property name="text">
          <string>C</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnSign">
         <property name="text">
          <string>±</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnSqrt">
         <property name="text">
          <string>√</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
      </layout>
     </item>
     <item row="4" column="0">
      <layout class="QHBoxLayout" name="horizontalLayout_3">
       <item>
        <widget class="QPushButton" name="btn7">
         <property name="text">
          <string>7</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btn8">
         <property name="text">
          <string>8</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btn9">
         <property name="text">
          <string>9</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnDiv">
         <property name="text">
          <string>/</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
        <widget class="QPushButton" name="btnPercent">
         <property name="text">
          <string>%</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
      </layout>
     </item>
     <item row="6" column="0">
      <layout class="QGridLayout" name="gridLayout">
       <item row="0" column="0">
        <widget class="QPushButton" name="btn1">
         <property name="text">
          <string>1</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="0" column="1">
        <widget class="QPushButton" name="btn2">
         <property name="text">
          <string>2</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="0" column="2">
        <widget class="QPushButton" name="btn3">
         <property name="text">
          <string>3</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="0" column="3">
        <widget class="QPushButton" name="btnSub">
         <property name="text">
          <string>-</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="0" column="4" rowspan="2">
        <widget class="QPushButton" name="btnEqual">
         <property name="enabled">
          <bool>true</bool>
         </property>
         <property name="acceptDrops">
          <bool>false</bool>
         </property>
         <property name="text">
          <string>=</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="1" column="0" colspan="2">
        <widget class="QPushButton" name="btn0">
         <property name="text">
          <string>0</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="1" column="2">
        <widget class="QPushButton" name="btnPoint">
         <property name="text">
          <string>.</string>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
       <item row="1" column="3">
        <widget class="QPushButton" name="btnAdd">
         <property name="text">
          <string>+</string>
         </property>
         <property name="autoDefault">
          <bool>false</bool>
         </property>
         <property name="default">
          <bool>false</bool>
         </property>
         <property name="flat">
          <bool>false</bool>
         </property>
        </widget>
       </item>
      </layout>
     </item>
    </layout>
   </widget>
  </widget>
  <widget class="QToolBar" name="mainToolBar">
   <attribute name="toolBarArea">
    <enum>TopToolBarArea</enum>
   </attribute>
   <attribute name="toolBarBreak">
    <bool>false</bool>
   </attribute>
  </widget>
  <widget class="QStatusBar" name="statusBar"/>
 </widget>
 <layoutdefault spacing="6" margin="11"/>
 <resources/>
 <connections/>
</ui>