具体要求如下：
实现代码：
<html>
<head>
<meta charset="utf-8">
<title>计算器</title>
<script>
function myck(type){
var num1 = document.getElementById("num1");
var num2 = document.getElementById("num2");
if(type==1){
// 计算操作
var result = parseInt(num1.value) + parseInt(num2.value);
alert(result);
document.getElementById("resultDiv").innerText ="最终计算结果："+ result;
}else if(type==2){
var result = parseInt(num1.value) - parseInt(num2.value);
alert(result);
document.getElementById("resultDiv").innerText ="最终计算结果："+ result;
}
else if(type==3){
var result = parseInt(num1.value) * parseInt(num2.value);
alert(result);
document.getElementById("resultDiv").innerText ="最终计算结果："+ result;
}
else if(type==4){
if(confirm("是否正确清空？")){
// 清空
num1.value = "";
num2.value = "";
document.getElementById("resultDiv").innerText="";
}
}
}
</script>
</head>
<body>
<div style="margin-top: 100px;margin-left: 500px;">
<span style="font-size: 60px;">计算器</span>
</div>
<div>
<div class="innerDiv" style="margin-left: 490px;">
数 字1：<input id="num1" type="number" placeholder="请输入数字1">
</div>
</div>
<div>
<div class="innerDiv" style="margin-left:490px;">
数 字2：<input id="num2" type="number" placeholder="请输入数字2">
</div>
</div>
<div>
<div style="margin-left: 500px;" class="innerDiv">
<input type="button" onclick="myck(1)" value="相 加">
<input type="button" onclick="myck(2)" value="相 减">
<input type="button" onclick="myck(3)" value="相 乘">
<input type="button" onclick="myck(4)" value="清 空">
</div>
</div>
<div id="resultDiv">
</div>
</body>
<style>
.innerDiv{
margin-left: 420px;
margin-top: 20px;
}
</style>
</html>
