<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type="text/javascript" src="js/JQ3.3.1.js"></script>
<script type="text/javascript">
$(function(){
var first = $("#first");// 获得ID为first标签的jQuery对象
var second = $("#second");// 获得ID为first标签的jQuery对象
var sumSP = $("#sumSP");// 获得ID为first标签的jQuery对象
first.change(function(){//第一个数
var num1 = first.val();// 取得first对象的值
var num2 = second.val();// 取得second对象的值
var sum = add(num1,num2);
sumSP.text(sum);
});
second.change(function(){//第二个数
var num1 = first.val();
var num2 = second.val();
var sum = add(num1,num2);
sumSP.text(sum);
});
});
function add(arg1,arg2){
var a1,a2,m;
try{
a1 = arg1.toString().split(".")[1].length
}catch(e){
a1 = 0;
}
try{
a2 = arg2.toString().split(".")[1].length
}catch(e){
a2 = 0;
}
m = Math.pow(10, Math.max(a1,a2));
return (arg1*m+arg2*m)/m;
}
</script>
</head>
<body>
<center>
<form action="">
第一个数：<input type="text" size="25" id="first" /><br /><br />
第二个数：<input type="text" size="25" id="second" /><br /><br />
它们的和：<span id="sumSP" style="color:red"></span>
</form>
</center>
</body>
</html>
