C# 如何获得JSON格式的响应和请求？

我没有得到JSON格式的输出。这是密码

--IService1.cs--

--Service1.svc.cs--

--web.config--

当我运行此服务时，我会将数据输入

但我希望结果是JSON格式的

---

示例：{currencycode:INR，DESCRIPTION:Indian Rupes，customercode:1001}，….

将[Serialize]属性添加到方法中

[ServiceContract]
public interface IService1
{
    [OperationContract]
    [WebInvoke(Method = "GET", RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.Bare, UriTemplate = "currency")]
    List<Employee> GetAllEmployeesMethod();

     [OperationContract]
     string TestMethod();

     [OperationContract]
     [WebInvoke(Method = "GET", RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json, UriTemplate = "players")]
     List<Person> GetPlayers();

}

public List<Employee> GetAllEmployeesMethod()
{
    List<Employee> mylist = new List<Employee>();

    using (SqlConnection conn = new SqlConnection("--connection string--"))
    {
        conn.Open();

        string cmdStr = String.Format("Select customercode,CurrencyCode,CurrencyDesc from Currency");
        SqlCommand cmd = new SqlCommand(cmdStr, conn);
        SqlDataReader rd = cmd.ExecuteReader();

        if (rd.HasRows)
        {
            while (rd.Read())
                mylist.Add(new Employee(rd.GetInt32(0), rd.GetString(1), rd.GetString(2)));
        }
        conn.Close();
    }


    return mylist;
}