这篇文章给大家分享的是有关JavaScript中如何实现简易计算器的内容。小编觉得挺实用的，因此分享给大家做个参考，一起跟随小编过来看看吧。
具体内容如下
<head>
<meta charset="UTF-8">
<title>Title</title>
<style type="text/css">
* {
padding: 0;
margin: 0;
}
li {
list-style: none;
}
body {
background: #940032;
}
#counter {
width: 500px;
height: 420px;
background: #939;
margin: 50px auto 0;
position: relative;
}
#counter h3 {
line-height: 42px;
padding-left: 15px;
font-size: 14px;
font-family: arial;
color: #ff3333;
}
#counter a {
font-weight: normal;
text-decoration: none;
color: #ff3333;
}
#counter a:hover {
text-decoration: underline;
}
#bg {
width: 280px;
height: 200px;
border: 3px solid #680023;
background: #990033;
filter: alpha(opacity=80);
opacity: 0.8;
position: absolute;
left: 50%;
top: 115px;
margin-left: -141px;
}
#counter_content {
width: 250px;
position: absolute;
top: 130px;
left: 130px;
z-index: 1;
}
#counter_content h4 {
margin-bottom: 10px;
}
#counter_content h4 input {
border: none;
width: 223px;
height: 30px;
line-height: 30px;
padding: 0 10px;
background: url(img/ico.png) no-repeat;
text-align: right;
color: #333;
font-size: 14px;
font-weight: bold;
}
#counter_content div {
width: 250px;
}
#counter_content input {
width: 60px;
height: 30px;
line-height: 30px;
float: left;
background: url(img/ico.png) no-repeat -303px 0;
text-align: center;
color: #fff;
cursor: pointer;
margin: 0 1px 4px 0;
border: 0;
}
#counter_content div > input:hover {
background: url(img/ico.png) no-repeat -243px 0;
}
#counter p {
width: 500px;
position: absolute;
bottom: 20px;
left: 0;
color: #ff3333;
text-align: center;
font-size: 12px;
}
</style>
</head>
<body>
<div id="counter">
<h3>简易计算</h3>
<div id="counter_content">
<h4><input id="input1" type="text" value="0"/></h4>
<div id="div1">
<input type="button" value="7" onclick="kick('7')"/>
<input type="button" value="8" onclick="kick('8')"/>
<input type="button" value="9" onclick="kick('9')"/>
<input type="button" value="+" onclick="kick('+')"/>
<input type="button" value="4" onclick="kick('4')"/>
<input type="button" value="5" onclick="kick('5')"/>
<input type="button" value="6" onclick="kick('6')"/>
<input type="button" value="-" onclick="kick('-')"/>
<input type="button" value="1" onclick="kick('1')"/>
<input type="button" value="2" onclick="kick('2')"/>
<input type="button" value="3" onclick="kick('3')"/>
<input type="button" value="*" onclick="kick('*')"/>
<input type="button" value="0" onclick="kick('0')"/>
<input type="button" value="C" onclick="kick('C')"/>
<input type="button" value="=" onclick="kick('=')"/>
<input type="button" value="/" onclick="kick('/')"/>
</div>
</div>
</div>
</body>
<script>
var showInput = document.getElementById("input1");
var isClear = false;
var tempStr = "";
var clacType = "";
var isContinue = true;
function kick(clickValue) {
switch (clickValue) {
case "=":
if (tempStr != "" && clacType != "") {
showInput.value = clac(tempStr, showInput.value, clacType);
isContinue = false;
clacType = "";
}
break;
case "+":
case "-":
case "*":
case "/":
//如果预存的操作符不为空 表示表示连续操作
if (clacType != "" && !isContinue) { //先执行计算
tempStr = clac(tempStr, showInput.value, clacType);
isClear = true;
clacType = clickValue;
} else {
tempStr = showInput.value; //点击操作符之后 预存字符
isClear = true;//表示点击了操作符
clacType = clickValue;//预存操作符
}
isContinue = true;
break;
case "C":
showInput.value = "0";
isClear = false;
tempStr = "";
clacType = "";
break;
default://普通的数字按钮点击
showInput.value = showInput.value == "0" ? "" : showInput.value;
isContinue = false;
if (isClear) {
showInput.value = "";
showInput.value += clickValue;
isClear = false;
} else {
showInput.value += clickValue;
}
break;
}
}
function clac(num1, num2, type) {
switch (type) {
case "+":
return Number(num1) + Number(num2);
case "-":
return Number(num1) - Number(num2);
case "*":
return Number(num1) * Number(num2);
case "/":
return Number(num1) / Number(num2);
default:
break;
}
}
</script>感谢各位的阅读！关于“JavaScript中如何实现简易计算器”这篇文章就分享到这里了，希望以上内容可以对大家有一定的帮助，让大家可以学到更多知识，如果觉得文章不错，可以把它分享出去让更多的人看到吧！
