javascript判断数据类型

整理一下javascript判断数据类型的函数

方法一：

 1 function isNumber(obj) {
 2     return Object.prototype.toString.call(obj) === "[object Number]";
 3 }
 4 function isString(obj) {
 5     return Object.prototype.toString.call(obj) === "[object String]";
 6 }
 7 function isBoolen(obj) {
 8     return Object.prototype.toString.call(obj) === "[object Boolen]";
 9 }
10 function isFunction(obj) {
11     return Object.prototype.toString.call(obj) === "[object Function]";
12 }
13 function isArray(obj) {
14     try {
15         Array.prototype.toString.call(obj);
16         return true;
17     } catch(e) {}
18     return false;
19 }
20 function isNaN(obj) {
21     return obj !== obj;
22 }
23 function isNull(obj) {
24     return obj === obj;
25 }
26 function isUndefined(obj) {
27     return obj === void 0;
28 }

 方法二：

 1 var class2type = {
 2     "[object HTMLDocument]": "Document",
 3     "[object HTMLCollection]": "NodeList",
 4     "[Object StaticNodeList]": "NodeList",
 5     "[obejct IXMLDOMNodeList]": "NodeList",
 6     "[object DOMWindow]": "Window",
 7     "[object global]": "window",
 8     "null": "Null",
 9     "NaN": "NaN",
10     "undefined": "Undefined"
11 },
12 toString = class2type.toString;
13 "Boolean,Number.String,Function.Array.Date,RegExp,Window,Document,Arguments,NodeList".replace(/\w+/g, function(name) {
14     class2type[ "[object " + name + "]" ] = name;
15 });
16 
17 type = function(obj, str) {
18     var result = class2type[ (obj == null || obj !== obj) ? obj : toString.call(obj) ] || obj.nodeName || "#";
19     if (result.charAt(0) === "#") {    //兼容旧版本浏览器与处理个别情况，如window.opera
20         //利用IE6、IE7、IE8 window == document 为true，document == window竟然为false的神奇特性
21         if (obj == obj.document && obj.document != obj ) {
22             result = 'Window';        //返回构造器名字
23         } else if (obj.nodeType === 9) {
24             result = 'Document';    //返回构造器名字
25         } else if (obj.callee) {
26             result = 'Arguments';    //返回构造器名字
27         } else if (isFinite(obj.length) && obj.item) {
28             result = 'NodeList';    //处理节点集合
29         } else {
30             result = toString.call(obj).slice(8, -1);
31         }
32     }
33     if (str) {
34         return str === result;
35     }
36     return result;
37 }

 

posted @ 2016-02-14 15:18  mitch  阅读(142)  评论(0)    收藏  举报