javascript forEach通用循环遍历方法_javascript技巧

var forEach = (function(){
//数组与伪数组的遍历
var _Array_forEach = function (array, block, context) {
if (array == null) return;
//对String进行特殊处理
if(typeof array == 'string'){
array = array.split('');
}
var i = 0,length = array.length;
for (;i };
//对象的遍历
var _Function_forEach = function (object, block, context) {
for (var key in object) {
//只遍历本地属性
if (object.hasOwnProperty(key)&&block.call(context, object[key], key, object)===false){
break;
}
}
};
return function(object, block, context){
if (object == null) return;
if (typeof object.length == "number") {
_Array_forEach(object, block, context);
}else{
_Function_forEach(object, block, context);
}
};
})()

//1:1 \n 2:2
forEach([1,2,3,4,5],function(el,index){
if(index>2){
return false;
}
alert(index+":"+el);
});
function print(el,index){
alert(index+":"+el);
}
//a:a \n b:b \n c:c
forEach({a:'a',b:'b',c:'c'},print);
//1:笨 \n 2:蛋 \n 3:的 \n 4:座 \n 5:右 \n 6:铭
forEach("笨蛋的座右铭",print);
function Person(name, age) {
this.name = name || "";
this.age = age || 0;
};
Person.prototype = new Person;
var fred = new Person("jxl", 22);
fred.language = "chinese";//极晚绑定
//name:jxl \n age:22 \n language:chinese
forEach(fred,print);