TOP

仿 jQuery.each() 方法遍历对象 (DOM、 Array、JSON、String)

发布时间： 2013-04-02

> 之前发表在开源中国：[http://my.oschina.net/pandao/blog/119300](http://my.oschina.net/pandao/blog/119300)

HTML:

```html
A
B
C
D
```

JavaScript：

```javascript
Object.prototype.each = String.prototype.each = function(fn) { 
    for (var i in this) {
       if (this.hasOwnProperty(i)) {   
            if (typeof(this[i]) == "object") {
                fn(i, this[i]);
            } else { 
                try { 
                    if (!this[0].nodeName) fn(i, this[i]);
                } catch (e) { 
                    fn(i, this[i]);
                }               
            }
        }
    }
}
 
// 遍历DOM对象
var arr = document.getElementsByTagName("span");
arr.each(function(index, obj) {
    console.log(index, obj, "className =>", obj.className);
});
 
// 遍历数组
[2,3,5].each(function(index, obj) {
    console.log(index, "=>", obj);
});
 
// 遍历 JSON 序列对象
var json = {
	name     : "pandao", 
	job      : "2D(Web Designer & Web Developer)", 
	length   : [1,2,3,4], 
	dom      : {nodeName : "span"}, 
	callback : function() {}
};

json.each(function(index, obj) {
 console.log(index, "=>", obj);
 
 // 嵌套遍历
 if (typeof (obj) == "object") {
 obj.each(function(i, o) {
 console.log(" ", index+"."+i, "=>", o);
 });
 }
});
 
// 遍历字符串
'<script type="text/javascript">'.each(function(index, str) {
 console.log(index, "=>", str);
});
```

TOP