C#中Json和类的相互转化

//在NuGet里下载安装  Newtonsoft.Json，再引用。
using Newtonsoft.Json;

//写一个用户类
public class UserDataInfo 
{
    public long UserID { get; set; }

    public string UserName { get; set; }

    public string UserSex { get; set; }

    public DateTime CreateDate { get; set; } 
}

//一、把用户类转成json
 UserDataInfo userDataInfo = new UserDataInfo()
 {
    UserID=1,
    UserName="zhangsan",
    UserSex="male",
    CreateDate=DateTime.Now
 };
string jsonStr = JsonConvert.SerializeObject(userDataInfo);

//二、把json转成用户类
string jsonText1 = "{'UserID':'1','UserName':'zhangsan','UserSex':'male','CreateDate':'" + DateTime.Now + "'}";
string jsonText2 = "{\"UserID\":\"1\",\"UserName\":\"zhangsan\",\"UserSex\":\"male\",\"CreateDate\":\"" + DateTime.Now + "\"}";           
UserDataInfo userDataInfoJson= JsonConvert.DeserializeObject<UserDataInfo>(jsonText1);