Javascript For/In 循环： 循环遍历对象的属性
 
var person={fname:"John",lname:"Doe",age:25};  
for (x in person)   {  
   txt=txt + person[x]; 
}  

结果：JohnDoe25  

jQuery jQuery.each() 遍历对象属性

var arr = ["one", "two", "three", "four", "five"];  

var obj = { one: 1, two: 2, three: 3, four: 4, five: 5 };  

遍历数组

var text = "Array ";  

jQuery.each(arr, function(i, val) {  

    text = text + " #Index:" + i + ":" + val;  

});  

console.log(text);  

//Array  #Index:0:one #Index:1:two #Index:2:three #Index:3:four #Index:4:five  

遍历对象
text = "Object ";  
jQuery.each(obj, function(i, val) {  

    text = text + "Key:" + i + ", Value:" + val; 

});  

console.log(text);  

//Object Key:one, Value:1Key:two, Value:2Key:three, Value:3Key:four, Value:4Key:five, Value:5  

相信才会最好