js 解析json

var json = {

   contry:{

    area:{

     man:"12万",

     women:"10万"

    }

   }

  };

//方式一：使用eval解析

  var obj = eval(json);

  alert(obj.constructor);

  alert(obj.contry.area.women);

  //方式二：使用Funtion函数

  var strJSON = "{name:'json name'}";//得到的JSON

  var obj = new Function("return" + strJSON)();//转换后的JSON对象

  alert(obj.name);//json name

  alert(obj.constructor);

//复杂一点的json数组数据的解析

  var value1 = [ 

    {"c01":"1","c02":"2","c03":"3","c04":"4","c05":"5","c06":"6","c07":"7","c08":"8","c09":"9"},

     {"c01":"2","c02":"4","c03":"5","c04":"2","c05":"8","c06":"11","c07":"21","c08":"1","c09":"12"},

    {"c01":"5","c02":"1","c03":"4","c04":"11","c05":"9","c06":"8","c07":"1","c08":"8","c09":"2"}

     ]; 

  var obj1 = eval(value1);

  alert(obj1[0].c01);

 //复杂一点的json的另一种形式

  var value2 = {

     "list":[

      {"password":"1230","username":"coolcooldool"},

      {"password":"thisis2","username":"okokok"}

      ],

     "array":[

      {"password":"1230","username":"coolcooldool"},

      {"password":"thisis2","username":"okokok"}

      ]

     };

  var obj2 = eval(value2);

  alert(obj2.list[0].password);

 }

 

4、eval

1这种形式将使得性能显著降低，因为它必须运行编译器

2eval函数还减弱了你的应用的安全性，因为它给被求值的文本赋予了太多的权力。就像with语句执行的方式一样，它降低了语言的性能

3Function构造器是eval的另一种形式，所以它同样也应该被避免使用。