javascript实现计算器功能

(编辑：jimmy 日期: 2024/11/26 浏览：3 次 )

本文实例为大家分享了javascript实现计算器功能的具体代码，供大家参考，具体内容如下

问题描述：

1、除法操作时，如果被除数为0，则结果为0
2、结果如果为小数，最多保留小数点后两位，如2 / 3 =0.67（显示0.67），1 / 2 = 0.5（显示0.5）

<!DOCTYPE html>
<html>
 <head>
 <meta charset="utf-8">
 <title>百度笔试0329</title>
 <style type="text/css">
 body, ul, li,select {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
 }
 ul,li {list-style: none;}
 .calculator {
  max-width: 300px;
  margin: 20px auto;
  border: 1px solid #eee;
  border-radius: 3px;
 }
 .cal-header {
  font-size: 16px;
  color: #333;
  font-weight: bold;
  height: 48px;
  line-height: 48px;
  border-bottom: 1px solid #eee;
  text-align: center;
 }
 .cal-main {
  font-size: 14px;
 }
 .cal-main .origin-value {
  padding: 15px;
  height: 40px;
  line-height: 40px;
  font-size: 20px;
  text-align: right;
  overflow: hidden;
  text-overflow:ellipsis;
  white-space: nowrap;
 }
 .cal-main .origin-type,
 .cal-main .target-type {
  padding-left: 5px;
  width: 70px;
  font-size: 14px;
  height: 30px;
  border: 1px solid #eee;
  background-color: #fff;
  vertical-align: middle;
  margin-right: 10px;
  border-radius: 3px;
 }
 .cal-keyboard {
  overflow: hidden;
 }
 .cal-items {
  overflow: hidden;
 }
 .cal-items li {
  user-select: none;
  float: left;
  display: inline-block;
  width: 75px;
  height: 75px;
  text-align: center;
  line-height: 75px;
  border-top: 1px solid #eee;
  border-left: 1px solid #eee;
  box-sizing: border-box;
 }
 li:nth-of-type(4n+1) {
  border-left: none;
 }
 li[data-action=operator] {
  background: #f5923e;
  color: #fff;
 }
 .buttons {
  float: left;
  width: 75px;
 }
 .buttons .btn {
  width: 75px;
  background-color: #fff;
  border-top: 1px solid #eee;
  border-left: 1px solid #eee;
  height: 150px;
  line-height: 150px;
  text-align: center;
 }
 .btn-esc {
  color: #ff5a34;
 }
 .btn-backspace {
  position: relative;
 }
 </style>
 </head>
 <body>
 <div class="calculator">
  <header class="cal-header">简易计算器</header>
  <main class="cal-main">
   <div class="origin-value">0</div>
   <div class="cal-keyboard">
    <ul class="cal-items">
     <li data-action="num">7</li>
     <li data-action="num">8</li>
     <li data-action="num">9</li>
     <li data-action="operator">÷</li>
     <li data-action="num">4</li>
     <li data-action="num">5</li>
     <li data-action="num">6</li>
     <li data-action="operator">x</li>
     <li data-action="num">1</li>
     <li data-action="num">2</li>
     <li data-action="num">3</li>
     <li data-action="operator">-</li>
     <li data-action="num">0</li>
     <li data-action="operator">清空</li>
     <li data-action="operator">=</li>
     <li data-action="operator">+</li>
    </ul>
   </div>
  </main>
 </div>
 <script type="text/javascript">
 var Calculator = {
  init: function () {
   var that = this;
   if (!that.isInited) {
    that.isInited = true;
    // 保存操作信息
    // total: Number, 总的结果
    // next: String, 下一个和 total 进行运算的数据
    // action: String, 操作符号
    that.data = {total: 0, next: '', action: ''};
    that.bindEvent();
   }
  },
  bindEvent: function () {
   var that = this;
   // 请补充代码：获取 .cal-keyboard 元素
   var keyboardEl = document.getElementsByClassName('cal-keyboard')[0]
   keyboardEl && keyboardEl.addEventListener('click', function (event) {
    // 请补充代码：获取当前点击的dom元素
    var target = event.target;
    // 请补充代码：获取target的 data-action 值
    var action = target.getAttribute('data-action');
    // 请补充代码：获取target的内容
    var value = target.innerHTML;
    if (action === 'num' || action === 'operator') {
     that.result(value, action === 'num');
    }
   });
  },
  result: function (action, isNum) {
   var that = this;
   var data = that.data;
   if (isNum) {
    data.next = data.next === '0' "_blank" href="https://www.jb51.net/Special/162.htm">计算器功能汇总 进行学习
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。

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