/**
* 数据
*/
var school = [{id:1,name:'一年级'},{id:2,name:'二年级'},{id:3,name:'三年级'}];

    /**
     * 对象转JSON字符串
     */
    var str = JSON.stringify(school);
    
    console.log(str)    
    
    //输出：[{"id":1,"name":"一年级"},{"id":2,"name":"二年级"},{"id":3,"name":"三年级"}]
    
    
    /**
     * JSON字符串转对象
     */
    var obj = JSON.parse(str);
    
    console.log(obj)   
    
    //输出：[Object, Object, Object]