C#實體類與XML相互轉換

1、實體類與XML相互轉換

將實體類轉換成XML需要使用XmlSerializer類的Serialize方法，將實體類序列化。

把XML轉換成相應的實體類，需要使用到XmlSerializer類的Deserialize方法，將XML進行反序列化。

創建XML序列化公共處理類（XmlSerializeHelper.cs）

using System;
using System.IO;
using System.Xml.Serialization;

/// <summary>
/// XML序列化公共處理類
/// </summary>
public static class XmlSerializeHelper
{
    /// <summary>
    /// 將實體對象轉換成XML
    /// </summary>
    /// <typeparam name="T">實體類型</typeparam>
    /// <param name="obj">實體對象</param>
    public static string XmlSerialize<T>(T obj)
    {
        try
        {
            using (StringWriter sw = new StringWriter())
            {
                Type t = obj.GetType();
                XmlSerializer serializer = new XmlSerializer(obj.GetType());
                serializer.Serialize(sw, obj);
                sw.Close();
                return sw.ToString();
            }
        }
        catch (Exception ex)
        {
            throw new Exception("將實體對象轉換成XML異常", ex);
        }
    }

    /// <summary>
    /// 將XML轉換成實體對象
    /// </summary>
    /// <typeparam name="T">實體類型</typeparam>
    /// <param name="strXML">XML</param>
    public static T DESerializer<T>(string strXML) where T : class
    {
        try
        {
            using (StringReader sr = new StringReader(strXML))
            {
                XmlSerializer serializer = new XmlSerializer(typeof(T));
                return serializer.Deserialize(sr) as T;
            }
        }
        catch (Exception ex)
        {
            throw new Exception("將XML轉換成實體對象異常", ex);
        }
    }
}

創建用戶信息類，用於示例使用。

/// <summary>
/// 用戶信息類
/// </summary>
public class UserInfo
{
    /// <summary>
    /// 編號
    /// </summary>
    public int ID { get; set; }

    /// <summary>
    /// 名稱
    /// </summary>
    public string Name { get; set; }

    /// <summary>
    /// 創建時間
    /// </summary>
    public DateTime? CreateTime { get; set; }
}

1.1 示例1：將List與XML相互轉換

/// <summary>
/// 將List與XML相互轉換
/// </summary>
public static void ListToXmlTest()
{
    //獲取用戶列表
    List<UserInfo> userList = GetUserList();

    //將實體對象轉換成XML
    string xmlResult = XmlSerializeHelper.XmlSerialize(userList);

    //將XML轉換成實體對象
    List<UserInfo> deResult = XmlSerializeHelper.DESerializer<List<UserInfo>>(xmlResult);
}

/// <summary>
/// 獲取用戶信息列表
/// </summary>
public static List<UserInfo> GetUserList()
{
    List<UserInfo> userList = new List<UserInfo>();
    userList.Add(new UserInfo() { ID = 1, Name = "張三", CreateTime = DateTime.Now });
    userList.Add(new UserInfo() { ID = 2, Name = "李四", CreateTime = DateTime.Now });
    userList.Add(new UserInfo() { ID = 2, Name = "王五" });
    return userList;
}

XML結果：

<?xml version="1.0" encoding="utf-16"?>
<ArrayOfUserInfo xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <UserInfo>
    <ID>1</ID>
    <Name>張三</Name>
    <CreateTime>2018-10-04T15:59:53.7761027+08:00</CreateTime>
  </UserInfo>
  <UserInfo>
    <ID>2</ID>
    <Name>李四</Name>
    <CreateTime>2018-10-04T15:59:54.9571044+08:00</CreateTime>
  </UserInfo>
  <UserInfo>
    <ID>2</ID>
    <Name>王五</Name>
    <CreateTime xsi:nil="true" />
  </UserInfo>
</ArrayOfUserInfo>

1.2 示例2：將DataTable與XML相互轉換

/// <summary>
/// 將DataTable與XML相互轉換
/// </summary>
public static void DataTableToXmlTest()
{
    //創建DataTable對象
    DataTable dt = CreateDataTable();

    //將DataTable轉換成XML
    string xmlResult = XmlSerializeHelper.XmlSerialize(dt);

    //將XML轉換成DataTable
    DataTable deResult = XmlSerializeHelper.DESerializer<DataTable>(xmlResult);
}

/// <summary>
/// 創建DataTable對象
/// </summary>
public static DataTable CreateDataTable()
{
    //創建DataTable
    DataTable dt = new DataTable("NewDt");

    //創建自增長的ID列
    DataColumn dc = dt.Columns.Add("ID", Type.GetType("System.Int32"));
    dt.Columns.Add(new DataColumn("Name", Type.GetType("System.String")));
    dt.Columns.Add(new DataColumn("CreateTime", Type.GetType("System.DateTime")));

    //創建數據
    DataRow dr = dt.NewRow();
    dr["ID"] = 1;
    dr["Name"] = "張三";
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    dr = dt.NewRow();
    dr["ID"] = 2;
    dr["Name"] = "李四";
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    dr = dt.NewRow();
    dr["ID"] = 3;
    dr["Name"] = "王五";
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    return dt;
}

XML結果：

<?xml version="1.0" encoding="utf-16"?>
<DataTable>
  <xs:schema id="NewDataSet" xmlns="" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
    <xs:element name="NewDataSet" msdata:IsDataSet="true" msdata:MainDataTable="NewDt" msdata:UseCurrentLocale="true">
      <xs:complexType>
        <xs:choice minOccurs="0" maxOccurs="unbounded">
          <xs:element name="NewDt">
            <xs:complexType>
              <xs:sequence>
                <xs:element name="ID" type="xs:int" minOccurs="0" />
                <xs:element name="Name" type="xs:string" minOccurs="0" />
                <xs:element name="CreateTime" type="xs:dateTime" minOccurs="0" />
              </xs:sequence>
            </xs:complexType>
          </xs:element>
        </xs:choice>
      </xs:complexType>
    </xs:element>
  </xs:schema>
  <diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
    <DocumentElement>
      <NewDt diffgr:id="NewDt1" msdata:rowOrder="0" diffgr:hasChanges="inserted">
        <ID>1</ID>
        <Name>張三</Name>
        <CreateTime>2018-10-04T16:06:10.8004082+08:00</CreateTime>
      </NewDt>
      <NewDt diffgr:id="NewDt2" msdata:rowOrder="1" diffgr:hasChanges="inserted">
        <ID>2</ID>
        <Name>李四</Name>
        <CreateTime>2018-10-04T16:06:10.8004082+08:00</CreateTime>
      </NewDt>
      <NewDt diffgr:id="NewDt3" msdata:rowOrder="2" diffgr:hasChanges="inserted">
        <ID>3</ID>
        <Name>王五</Name>
        <CreateTime>2018-10-04T16:06:10.8004082+08:00</CreateTime>
      </NewDt>
    </DocumentElement>
  </diffgr:diffgram>
</DataTable>

2、序列化常用Attribute講解說明

[XmlRootAttribute("MyCity", Namespace="abc.abc", IsNullable=false)]     // 當該類爲Xml根節點時，以此爲根節點名稱。
public class City

[XmlAttribute("AreaName")]    // 表現爲Xml節點屬性。<... AreaName="..."/>
public string Name

[XmlElementAttribute("AreaId", IsNullable = false)]    // 表現爲Xml節點。<AreaId>...</AreaId>
public string Id

[XmlArrayAttribute("Areas")]    // 表現爲Xml層次結構，根爲Areas，其所屬的每個該集合節點元素名爲類名。<Areas><Area ... /><Area ... /></Areas>
public Area[] Areas

[XmlElementAttribute("Area", IsNullable = false)]    // 表現爲水平結構的Xml節點。<Area ... /><Area ... />...
public Area[] Areas

[XmlIgnoreAttribute]    // 忽略該元素的序列化。

把這些屬性與model類的相關屬性，配合使用，就可以自由設置相關XML的具體格式了。

綜合示例：將班級信息序列化成XML

示例要求：

（1）每個XML節點以“My”開頭。

（2）班級ID和學生ID字段以XML節點屬性表現，其它字段以XML節點的形式表現。

（3）由於學生的郵箱涉及敏感信息，所以不參與序列化。

2.1 創建班級信息類（ClassInfo.cs）

using System.Collections.Generic;
using System.Xml.Serialization;

/// <summary>
/// 班級信息類
/// </summary>
[XmlRootAttribute("MyClassInfo", Namespace = "ABC_123", IsNullable = false)] 
public class ClassInfo
{
    /// <summary>
    /// 班級ID
    /// </summary>
    [XmlAttribute("MyClassID")]
    public int ClassID { get; set; }

    /// <summary>
    /// 班級名稱
    /// </summary>
    [XmlElementAttribute("MyClassName", IsNullable = false)] 
    public string ClassName { get; set; }

    /// <summary>
    /// 班長人
    /// </summary>
    [XmlElementAttribute("MyTeacher", IsNullable = false)] 
    public string Teacher { get; set; }

    /// <summary>
    /// 學生列表
    /// </summary>
    [XmlArrayAttribute("MyStudents")]  
    public List<Student> StudentList { get; set; }
}

2.2 創建學生信息類（Student.cs）

using System.Xml.Serialization;

/// <summary>
/// 學生信息類
/// </summary>
[XmlRootAttribute("MyStudent", IsNullable = false)] 
public class Student
{
    /// <summary>
    /// 學生ID
    /// </summary>
    [XmlAttribute("MyStuID")]
    public int StuID { get; set; }

    /// <summary>
    /// 學生名稱
    /// </summary>
    [XmlElementAttribute("MyStuName", IsNullable = false)] 
    public string StuName { get; set; }

    /// <summary>
    /// 性別
    /// </summary>
    [XmlElementAttribute("MySex", IsNullable = false)] 
    public string Sex { get; set; }

    /// <summary>
    /// 郵箱
    /// </summary>
    [XmlIgnoreAttribute] 
    public string Email { get; set; }
}

2.3 將班級信息轉換成XML

/// <summary>
/// 將班級信息轉換成XML
/// </summary>
public static void ClassInfoToXml()
{
    //獲取班級信息
    ClassInfo classInfo = GetClassInfo();

    //將班級信息轉換成XML
    string classXml = XmlSerializeHelper.XmlSerialize(classInfo);
}

/// <summary>
/// 獲取班級信息
/// </summary>
public static ClassInfo GetClassInfo()
{
    //創建班級信息
    ClassInfo classInfo = new ClassInfo();
    classInfo.ClassID = 1;
    classInfo.ClassName = "高一（5）班";
    classInfo.Teacher = "李老師";

    //創建學生列表
    List<Student> studentList = new List<Student>();
    studentList.Add(new Student() { StuID = 1, StuName = "張三", Sex = "男", Email = "[email protected]" });
    studentList.Add(new Student() { StuID = 2, StuName = "李四", Sex = "女", Email = "[email protected]" });
    studentList.Add(new Student() { StuID = 3, StuName = "王五", Sex = "男", Email = "[email protected]" });
    classInfo.StudentList = studentList;

    return classInfo;
}

XML結果：

<?xml version="1.0" encoding="utf-16"?>
<MyClassInfo xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" MyClassID="1" xmlns="ABC_123">
  <MyClassName>高一（5）班</MyClassName>
  <MyTeacher>李老師</MyTeacher>
  <MyStudents>
    <Student MyStuID="1">
      <MyStuName>張三</MyStuName>
      <MySex>男</MySex>
    </Student>
    <Student MyStuID="2">
      <MyStuName>李四</MyStuName>
      <MySex>女</MySex>
    </Student>
    <Student MyStuID="3">
      <MyStuName>王五</MyStuName>
      <MySex>男</MySex>
    </Student>
  </MyStudents>
</MyClassInfo>