我正在嘗試使用 DataContractSerializer 反序列化以下 XML。<?xml version="1.0" encoding="utf-8"?><order>  <header>    <cust>1</cust>    <bill>2</bill>    <ship>3</ship>    <nbr>123456</nbr>  </header>  <details>    <detail>      <nbr>123456</nbr>      <part>1227</part>      <qty>2</qty>    </detail>  </details></order>我在反序列化子<detail></detail>段時遇到了困難，這始終是null. 我的班級結(jié)構(gòu)如下：[DataContract(Name = "order", Namespace ="")]public class Order{    [DataMember(Name = "header", Order = 0)]    public Head head { get; set; }    [DataMember(Name = "details", Order = 1)]    public Details details { get; set; }    public Order()    {    }}[DataContract(Name = "header", Namespace ="")]public class Head{    [DataMember(Name = "cust", Order = 0)]    public string customerNbr { get; set; }    [DataMember(Name = "bill", Order = 1)]    public string billNbr { get; set; }    [DataMember(Name = "ship", Order = 2)]    public string shipmentNbr { get; set; }    [DataMember(Name = "nbr", Order = 3)]    public string orderNbr { get; set; }    public Head()    {    }}[DataContract(Name = "details")]public class Details{    [DataMember(Name = "detail", Order = 0)]    public List<Detail> DetailList { get; set; }    public Details()    {        this.DetailList = new List<Detail>();    }}[DataContract(Name = "detail")]public class Detail{    [DataMember(Name = "nbr", Order = 0)]    public string orderNbr { get; set; }    [DataMember(Name = "part", Order = 1)]    public string partNbr { get; set; }    [DataMember(Name = "qty", Order = 2)]    public decimal orderQty { get; set; }    public Detail()    {    }}在我的主程序中，我正在閱讀 XML 文檔并使用以下內(nèi)容對其進行反序列化：XDocument readDoc = XDocument.Load(fileName);Order createOrder = null;DataContractSerializer ser = new DataContractSerializer(typeof(Order));createOrder = (Order)ser.ReadObject(readDoc.CreateReader());我該怎么做才能使詳細信息段正確反序列化？