//父类可序列化
    [Serializable]
    [DataContract]
    public class QueryParameters
    {
        [DataMember]
        public string ApplicantName { get; set; }
        [DataMember]
        public string IdentifyNumber { get; set; }
    }

//继承类也可序列化
    [Serializable]
    [DataContract]
    public class AntiFraudRequestParamters : QueryParameters
    {
        [DataMember]
        public string QueryEmployee { get; set; }
        [DataMember]
        public string QueryReason { get; set; }
        [DataMember]
        public string QueryEndDate { get; set; }

    }

var bhParas = new AntiFraudRequestParamters ();
            string entity = JsonConvert.SerializeObject(bhParas, Formatting.None);
//NewTonSoft.Json序列化得到结果：
{
    "ApplicantName": null,
    "IdentifyNumber": null,
    "QueryEmployee": null,
    "QueryReason": null,
    "QueryEndDate": null
}

//继承类不加可序列化
    public class AntiFraudRequestParamters : QueryParameters
    {
        public string QueryEmployee { get; set; }
        public string QueryReason { get; set; }
        public string QueryEndDate { get; set; }

    }
            var bhParas = new AntiFraudRequestParamters ();
            string entity = JsonConvert.SerializeObject(bhParas, Formatting.None);
//NewTonSoft.Json序列化得到结果：
{
    "ApplicantName": null,
    "IdentifyNumber": null
}
//结果没有得到继承类加的三个属性