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。