json获取元素数量

 var keleyijson={"plug1":"myslider","plug2":"zonemenu"}

 function JSONLength(obj) {
 var size = 0, key;
 for (key in obj) {
 if (obj.hasOwnProperty(key)) size++;
 }
 return size;
 };
 document.write("json对象的元素个数是："+JSONLength(keleyijson));//结果为2

在获取一组json，看其返回结果

 var keleyijson={

 "model": [
 { "firstName": "Brett", "lastName":"McLaughlin", "email": "aaaa" },

 { "firstName": "Jason", "lastName":"Hunter", "email": "bbbb" }
 ],

 "girl": [
 { "firstName": "Brett", "lastName":"McLaughlin", "email": "aaaa" },

 { "firstName": "Jason", "lastName":"Hunter", "email": "bbbb" }
 ],

 "zachary": [
 { "firstName": "Brett", "lastName":"McLaughlin", "email": "aaaa" },

 { "firstName": "Jason", "lastName":"Hunter", "email": "bbbb" }
 ],

 "lite": [
 { "firstName": "Brett", "lastName":"McLaughlin", "email": "aaaa" },

 { "firstName": "Jason", "lastName":"Hunter", "email": "bbbb" }
 ]

 }

 function JSONLength(obj) {
 var size = 0, key;
 for (key in obj) {
 if (obj.hasOwnProperty(key)) size++;
 }
 return size;
 };
 document.write("json对象的元素个数是："+JSONLength(keleyijson));