js实现的八点拖动修改div大小的代码

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<title>Resize</title> 
<style type="text/css"> 
#rRightDown,#rLeftDown,#rLeftUp,#rRightUp,#rRight,#rLeft,#rUp,#rDown{ 
position:absolute;background:#C00;width:6px;height:6px;z-index:5;font-size:0;} 
#rLeftDown,#rRightUp{cursor:ne-resize;} 
#rRightDown,#rLeftUp{cursor:nw-resize;} 
#rRight,#rLeft{cursor:e-resize;} 
#rUp,#rDown{cursor:n-resize;} 
#rRightDown{ bottom:-3px; right:-3px;} 
#rLeftDown{ bottom:-3px; left:-3px;} 
#rRightUp{ top:-3px; right:-3px;} 
#rLeftUp{ top:-3px; left:-3px;} 
#rRight{ right:-3px; top:50%} 
#rLeft{ left:-3px; top:50%} 
#rUp{ top:-3px; left:50%} 
#rDown{ bottom:-3px; left:50%} 
</style> 
</head> 
<body> 
<div id='ss' style="height:100px; width:100px; border:1px solid #000000; position:absolute; left:200px; top:200px;" > 
<div id="rRightDown"> </div> 
<div id="rLeftDown"> </div> 
<div id="rRightUp"> </div> 
<div id="rLeftUp"> </div> 
<div id="rRight"> </div> 
<div id="rLeft"> </div> 
<div id="rUp"> </div> 
<div id="rDown"></div> 
</div> 
<script> 
var Sys = (function(ua){ 
    var s = {}; 
    s.IE = ua.match(/msie ([\d.]+)/)?true:false; 
    s.Firefox = ua.match(/firefox\/([\d.]+)/)?true:false; 
    s.Chrome = ua.match(/chrome\/([\d.]+)/)?true:false; 
    s.IE6 = (s.IE&&([/MSIE (\d)\.0/i.exec(navigator.userAgent)][0][1] == 6))?true:false; 
    s.IE7 = (s.IE&&([/MSIE (\d)\.0/i.exec(navigator.userAgent)][0][1] == 7))?true:false; 
    s.IE8 = (s.IE&&([/MSIE (\d)\.0/i.exec(navigator.userAgent)][0][1] == 8))?true:false; 
    return s; 
})(navigator.userAgent.toLowerCase());

var $ = function (id) { 
    return document.getElementById(id); 
};

var Css = function(e,o){ 
    for(var i in o) 
    e.style[i] = o[i]; 
};

var Extend = function(destination, source) { 
    for (var property in source) { 
        destination[property] = source[property]; 
    } 
};

var Bind = function(object, fun) { 
    var args = Array.prototype.slice.call(arguments).slice(2); 
    return function() { 
        return fun.apply(object, args); 
    } 
};

var BindAsEventListener = function(object, fun) { 
    var args = Array.prototype.slice.call(arguments).slice(2); 
    return function(event) { 
        return fun.apply(object, [event || window.event].concat(args)); 
    } 
};

var CurrentStyle = function(element){ 
    return element.currentStyle || document.defaultView.getComputedStyle(element, null); 
};

function addListener(element,e,fn){ 
    element.addEventListener?element.addEventListener(e,fn,false):element.attachEvent("on" + e,fn); 
}; 
function removeListener(element,e,fn){ 
    element.removeEventListener?element.removeEventListener(e,fn,false):element.detachEvent("on" + e,fn) 
};

var Class = function(properties){ 
    var _class = function(){return (arguments[0] !== null && this.initialize && typeof(this.initialize) == 'function') ? this.initialize.apply(this, arguments) : this;}; 
    _class.prototype = properties; 
    return _class; 
};

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]

js实现的八点拖动修改div大小的代码_javascript技巧