将各种类型或对象都转变为数组

jQuery的makeArray有其局限性（1.3.4还有bug），我自己实现了一个，不过涉及N多辅助方法。
      var dom = {},
      _toString = Object.prototype.toString,
      _slice = Array.prototype.slice;
      dom.is = function(obj,type) {
        return _toString.call(obj).match(/^\[object\s(.*)\]$/)[1] === type;
      }
      dom.isArray = function (obj) {
        return dom.is(obj,"Array");
      }
      dom.isNumber = function (obj) {
        return dom.is(obj,"Number");
      }
      dom.isString = function (obj) {
        return dom.is(obj,"String");
      }
      dom.isArrayLike =  function (obj) {//包括Array
        if(dom.isArray(obj) || obj.callee) return true;
        if(dom.is(obj,'NodeList')) return true;
        if(dom.is(obj,'HTMLCollection')) return true;
        //不能为字符串,不能为window,具有length属性
        if(dom.isNumber(obj.length) && !dom.isString(obj) && !obj.eval){
          if(obj.nextNode || obj.item)
            return true;
          var n = obj.length - 1 
早期尝试使用Ext.isIterable，不过它有点小BUG，如放一个函数进去，它会返回undefined，好歹返回false嘛，另对于用户自定义的类数组对象无法检测，残念！不过我的isArrayLike也不完美，自定义的东西随意性太大了，暂时没办法一网打尽……以后慢慢改进！
下面是测试：
 
<!doctype html>
<html dir="ltr" lang="zh-CN" >
  <head >
    <meta charset="utf-8"/>
    <title>toArray函数 by司徒正美</title>
    <script src="http://common.cnblogs.com/script/jquery.js" type="text/javascript"></script>
    <script type="text/javascript" charset="utf-8">
       var dom = {},
      _toString = Object.prototype.toString,
      _slice = Array.prototype.slice;
      dom.is = function(obj,type) {
        return _toString.call(obj).match(/^\[object\s(.*)\]$/)[1] === type;
      }
      dom.isArray = function (obj) {
        return dom.is(obj,"Array");
      }
      dom.isNumber = function (obj) {
        return dom.is(obj,"Number");
      }
      dom.isString = function (obj) {
        return dom.is(obj,"String");
      }
      dom.isArrayLike =  function (obj) {//包括Array
        if(dom.isArray(obj) || obj.callee) return true;
        if(dom.is(obj,'NodeList')) return true;
        if(dom.is(obj,'HTMLCollection')) return true;
        //不能为字符串,不能为window,具有length属性
        if(dom.isNumber(obj.length) && !dom.isString(obj) && !obj.eval){
          if(obj.nextNode || obj.item)
            return true;
          var n = obj.length - 1  
<p><button type="button" title="runcode1" class="runcode">运行代码</button></p> 
<pre class="brush:javascript;gutter:false;toolbar:false;">
//2010.2.27更新
        var is = function(obj,type){
             return String(Object.prototype.toString.call(obj)).slice(8,-1) === type;
        }
        var toArray = function (obj) {
            var result = [];
            if ( obj != null ) {
                //对于普通对象，window对象，字符串，函数，select元素节点
                //window.length为frames.length,function.length为其形参的长度,select.length为其options.length
                if ( obj.length == null || is(obj,"String") || is(obj,"Function") || obj.eval || obj.nodeType ) {
                    result = [obj]
                } else {
                    try{//IE下，slice在转换HTMLCollection,NodeList,IXMLDOMNodeList 会失败
                        result = slice.call(obj);
                    } catch(e){
                        var i = obj.length
                        while( i )
                            result[--i] = obj[i];
                    }
                }
            }
            return result;
        }
</pre>