jquery字符串转json

var data;
var json='[{"CityId":18,"CityName":"西安","ProvinceId":27,"CityOrder":1},{"CityId":53,"CityName":"广州","ProvinceId":27,"CityOrder":1}]';
eval("data="+json); 
alert(data); 



$(data).each(function(){ 
    alert(this.CityId+" "+this.CityName); 
});