<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
#show {
width: 232px;
height: 80px;
color: white;
border-radius: 5px 5px 0 0;
background-color: rgba(127, 128, 127, 1);
text-align: right;
border: none;
font-size: 45px;
outline: none;
}
table {
border: 1px solid black;
border-collapse: collapse;
width: 234px;
text-align: center;
font-size: 30px;
}
td {
height: 55px;
width: 57.5px;
background-color: wheat;
}
td:active {
background-color: coral;
}
.aperation {
background-color: rgb(245, 146, 62);
color: white;
}
#ape {
background-color: wheat;
color: #000000;
}
</style>
</head>
<body>
<div id="">
<input type="" id="show" />
<table border="1">
<tr>
<td id="clear">AC</td>
<td>+/-</td>
<td class="aperation" id="ape">%</td>
<td class="aperation">/</td>
</tr>
<tr>
<td class="num">7</td>
<td class="num">8</td>
<td class="num">9</td>
<td class="aperation">*</td>
</tr>
<tr>
<td class="num">4</td>
<td class="num">5</td>
<td class="num">6</td>
<td class="aperation">-</td>
</tr>
<tr>
<td class="num">1</td>
<td class="num">2</td>
<td class="num">3</td>
<td class="aperation">+</td>
</tr>
<tr>
<td colspan="2" class="num">0</td>
<td>.</td>
<td class="aperation" id="result">=</td>
</tr>
</table>
</div>
</body>
<script type="text/javascript">
//获取数字的集合
var nums = document.getElementsByClassName("num");
//获取操作符的集合
var options = document.getElementsByClassName("aperation");
//获取等号
var result = document.getElementById("result");
//获取归0
var clear = document.getElementById("clear");
//获取展示框
var show = document.getElementById("show");
//声明用于保存内容的三个变量
var numValue = ""; //存储数字
var optionC = ""; //存储操作符
var numTemp = ""; //存储暂存值
//点击数字键时 触发事件
for(var i = 0; i < nums.length; i++) {
nums[i].onclick = function() {
if(numValue == "0") {
numValue = "";
}
numValue += this.innerHTML;
show.value = numValue;
}
}
//点击操作键触发事件
for(var i = 0; i < options.length - 1; i++) {
options[i].onclick = function() {
//先存储之前记录的数字
numTemp = numValue;
//记录操作符
optionC = this.innerHTML;
//清除原有记录的数字
numValue = "";
}
}
//等号操作
result.onclick = function() {
show.value = eval(numTemp + optionC + numValue);
}
//清零操作
clear.onclick = function() {
show.value = "0";
numValue = "";
optionC = "";
numTemp = "";
}
</script>
</html>