js eval 解析字符串

//带变量的字符串
var str  = 'var a=1; var b=2;';
eval(str);
alert(a+b);//结果 3；


//数组字符串
var arrStr = "[1,2,3,4]";

eval(arrStr);

arrStr = [1,2,3,4];//转化结果

//json对象字符串
var jsonStr = "{name:'xiao',sex:'man'}";

eval(jsonStr);

arrStr ={name:'xiao',sex:'man'};//转化结果

//json 对象转化为json 字符串

  var student = new Object();

  student.name = "Lanny";

  student.age = "25";

  student.location = "China";

  var json = JSON.stringify(student);

  alert(student);