让html的text输入框只能输入数字和1个小数点(0-59之间可改)

<html> 
<head> 
<title>text 数字</title> 
<meta http-equiv="Content-Type" content="text/html; charset=gbk"> 
</head> 
<script type="text/javascript"> 
function check(event) { 
var e = window.event || event; 
var target = e.srcElement || e.target; 
var k = e.keyCode; 
if(isFunKey(k)) { 
return true; 
} 
var c = getChar(k); 
if(target.value.length == '' && (c == '-' || c == '+')) { 
return true; 
} 
if(isNaN(target.value + getChar(k))) { 
return false; 
} 
return true; 
} 
function isFunKey(code) { 
// 8 --> Backspace 
// 35 --> End 
// 36 --> Home 
// 37 --> Left Arrow 
// 39 --> Right Arrow 
// 46 --> Delete 
// 112~123 --> F1~F12 
var funKeys = [8, 35, 36, 37, 39, 46]; 
for(var i = 112; i <= 123; i++) { 
funKeys.push(i); 
} 
for(var i = 0; i < funKeys.length; i++) { 
if(funKeys[i] == code) { 
return true; 
} 
} 
return false; 
} 
function getChar(k) { 
if(k >= 48 && k <= 57) { 
return String.fromCharCode(k); 
} 
if(k >= 96 && k <= 105) { 
return String.fromCharCode(k - 48); 
} 
if(k == 110 || k == 190 || k== 188 ) { 
return "."; 
} 
if(k == 109 || k == 189) { 
return "-"; 
} 
if(k == 107 || k == 187) { 
return "+"; 
} 
return "#"; 
} 
</script> 
<style type="text/css"> 
textarea { 
width: 200px; 
height: 80px; 
} 
span { 
color: #ff0000; 
} 
</style> 
<body> 
<input style="ime-mode:disabled;" onpaste="return false" onkeydown="return check(event)" onkeyup="if(isNaN(this.value)||this.value<0||this.value>59) this.value='0'"> 
</body> 
</html>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]