QT实现计算器（包含科学计算与进制转换）

#include "mainwindow.h" #include "ui_mainwindow.h" #include "mycal.h" #include <QMessageBox> MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { ui->setupUi(this); ui->input->setAlignment(Qt::AlignRight); //输入框右对齐 ui->formula->setAlignment(Qt::AlignRight); //表达式框右对齐 ui->histoyText->setAlignment(Qt::AlignRight); //历史记录框右对齐 ui->input->setText("0"); //输入框初始值显示0 ui->histoyText->setText("尚无历史记录"); //历史记录初始值设置 clearall = false; //清除标志 eq = false; //是否有历史记录 } MainWindow::~MainWindow() { delete ui; } void MainWindow::on_one_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"1"); } void MainWindow::on_two_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"2"); } void MainWindow::on_three_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"3"); } void MainWindow::on_four_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"4"); } void MainWindow::on_five_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"5"); } void MainWindow::on_six_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"6"); } void MainWindow::on_seven_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"7"); } void MainWindow::on_eight_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"8"); } void MainWindow::on_nine_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"9"); } void MainWindow::on_zero_clicked() { if(ui->input->text() == "0") { ui->input->clear(); } QString s = ui->formula->text(); int n = s.length(); if(n != 0 && s[n - 1] == ')') //数字前不能出现右括号 { QMessageBox::information(NULL, "错误","数字前不能为右括号!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->input->setText(ui->input->text()+"0"); } void MainWindow::on_pushButton_3_clicked() //小数点 { QString s = ui->input->text(); //获取之前输入的数字 int n = s.length(); if(n != 0 && (s[n - 1] > '9' || s[n - 1] < '0')) //小数点前没有数字 { QMessageBox::information(NULL, "错误","小数点前应输入数字!", QMessageBox::Yes,QMessageBox::Yes); return; } else if(n == 0) //不能小数点开头 { QMessageBox::information(NULL, "错误","小数点前为空!", QMessageBox::Yes,QMessageBox::Yes); return; } for(int i = 0; i < n; ++ i) { if(s[i] == '.') //这个数字前是否还有小数点 { QMessageBox::information(NULL, "错误","只能有一个小数点!", QMessageBox::Yes,QMessageBox::Yes); return; break; } } ui->input->setText(ui->input->text()+"."); } void MainWindow::on_symbol_clicked() //正负号 { if(ui->input->text()[0] == '-') //是负数 { QString str = ui->input->text(); QString s; for(int i = 1, j = 0; i < str.length(); ++i, ++j) s[j] = str[i]; //去掉负号，变为正数 ui->input->setText(s); } else ui->input->setText("-"+ui->input->text()); //为正数，加上负号 } void MainWindow::on_rightB_clicked() //左括号 { if(ui->input->text()!="0") ui->formula->setText(ui->formula->text() + ui->input->text()); QString s = ui->formula->text(); int n = s.length(); //左括号前不能有右括号，数字和小数点出现 if(n != 0 &&(s[n - 1] == ')' || s[n - 1] == '.' || (s[n - 1] >= '0' && s[n - 1] <= '9'))) { QMessageBox::information(NULL, "错误","括号前输入非法!", QMessageBox::Yes,QMessageBox::Yes); return; } ui->formula->setText(ui->formula->text() + "("); ui->input->setText("0"); } void MainWindow::on_LeftB_clicked() //右括号 { if(ui->input->text()!="0") ui->formula->setText(ui->formula->text() + ui->input->text()); QString s = ui->formula->text(); int n = s.length(); if(n == 0) { QMessageBox::information(NULL, "错误","右括号前不能为空!",