JavaScript浮点数计算bug-优快云博客

程序内容来源：http://www.2cto.com/kf/201502/376763.html，也不晓得它是不是从哪儿转的

亲测四个函数可用，留着了：

<!DOCTYPE html>
<html>
	<head>
	<script src="jquery-1.5.1.js"></script>
	<script>
		function add(a, b) {
		    var c, d, e;
		    try {
		        c = a.toString().split(".")[1].length;
		    } catch (f) {
		        c = 0;
		    }
		    try {
		        d = b.toString().split(".")[1].length;
		    } catch (f) {
		        d = 0;
		    }
		    return e = Math.pow(10, Math.max(c, d)), (mul(a, e) + mul(b, e)) / e;
		}
		
		function sub(a, b) {
		    var c, d, e;
		    try {
		        c = a.toString().split(".")[1].length;
		    } catch (f) {
		        c = 0;
		    }
		    try {
		        d = b.toString().split(".")[1].length;
		    } catch (f) {
		        d = 0;
		    }
		    return e = Math.pow(10, Math.max(c, d)), (mul(a, e) - mul(b, e)) / e;
		}
		
		function mul(a, b) {
		    var c = 0,
		        d = a.toString(),
		        e = b.toString();
		    try {
		        c += d.split(".")[1].length;
		    } catch (f) {}
		    try {
		        c += e.split(".")[1].length;
		    } catch (f) {}
		    return Number(d.replace(".", "")) * Number(e.replace(".", "")) / Math.pow(10, c);
		}
		
		function div(a, b) {
		    var c, d, e = 0,
		        f = 0;
		    try {
		        e = a.toString().split(".")[1].length;
		    } catch (g) {}
		    try {
		        f = b.toString().split(".")[1].length;
		    } catch (g) {}
		    return c = Number(a.toString().replace(".", "")), d = Number(b.toString().replace(".", "")), mul(c / d, Math.pow(10, f - e));
		}
		
		$(document).ready(function(){
			var index = 1;
			var num = 12.35;
			var result;
			$("#btn").click(function(){
				result = mul(index,num);
				$("#result").text(index++ + " x " + num + " = " + result + " " + result.toFixed(1));
			});
		});
	</script>
	</head>
	
	<body>
	
	<button id="btn">click</button>
	<span id="result">0</span>
	</body>
</html>