C#实体类与XML相互转换

男娘i 2021-09-16 13:48 431阅读 0赞

**1、实体类与XML相互转换**

将实体类转换成XML需要使用XmlSerializer类的Serialize方法，将实体类序列化。

把XML转换成相应的实体类，需要使用到XmlSerializer类的Deserialize方法，将XML进行反序列化。

创建XML序列化公共处理类（XmlSerializeHelper.cs）

using System;
    using System.IO;
    using System.Xml.Serialization;
    
    /// <summary>
    /// XML序列化公共处理类
    /// </summary>
    public static class XmlSerializeHelper
    {
        /// <summary>
        /// 将实体对象转换成XML
        /// </summary>
        /// <typeparam name="T">实体类型</typeparam>
        /// <param name="obj">实体对象</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("将实体对象转换成XML异常", ex);
            }
        }
    
        /// <summary>
        /// 将XML转换成实体对象
        /// </summary>
        /// <typeparam name="T">实体类型</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("将XML转换成实体对象异常", ex);
            }
        }
    }

创建用户信息类，用于示例使用。

/// <summary>
    /// 用户信息类
    /// </summary>
    public class UserInfo
    {
        /// <summary>
        /// 编号
        /// </summary>
        public int ID { get; set; }
    
        /// <summary>
        /// 名称
        /// </summary>
        public string Name { get; set; }
    
        /// <summary>
        /// 创建时间
        /// </summary>
        public DateTime? CreateTime { get; set; }
    }

**1.1 示例1：将List与XML相互转换**

/// <summary>
    /// 将List与XML相互转换
    /// </summary>
    public static void ListToXmlTest()
    {
        //获取用户列表
        List<UserInfo> userList = GetUserList();
    
        //将实体对象转换成XML
        string xmlResult = XmlSerializeHelper.XmlSerialize(userList);
    
        //将XML转换成实体对象
        List<UserInfo> deResult = XmlSerializeHelper.DESerializer<List<UserInfo>>(xmlResult);
    }
    
    /// <summary>
    /// 获取用户信息列表
    /// </summary>
    public static List<UserInfo> GetUserList()
    {
        List<UserInfo> userList = new List<UserInfo>();
        userList.Add(new UserInfo() { ID = 1, Name = "张三", 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结果：

<?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>张三</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：将DataTable与XML相互转换**

/// <summary>
    /// 将DataTable与XML相互转换
    /// </summary>
    public static void DataTableToXmlTest()
    {
        //创建DataTable对象
        DataTable dt = CreateDataTable();
    
        //将DataTable转换成XML
        string xmlResult = XmlSerializeHelper.XmlSerialize(dt);
    
        //将XML转换成DataTable
        DataTable deResult = XmlSerializeHelper.DESerializer<DataTable>(xmlResult);
    }
    
    /// <summary>
    /// 创建DataTable对象
    /// </summary>
    public static DataTable CreateDataTable()
    {
        //创建DataTable
        DataTable dt = new DataTable("NewDt");
    
        //创建自增长的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")));
    
        //创建数据
        DataRow dr = dt.NewRow();
        dr["ID"] = 1;
        dr["Name"] = "张三";
        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结果：

<?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>张三</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讲解说明**

\[XmlRootAttribute("MyCity", Namespace="abc.abc", IsNullable=false)\]     // 当该类为Xml根节点时，以此为根节点名称。  
public class City

\[XmlAttribute("AreaName")\]    // 表现为Xml节点属性。<... AreaName="..."/>  
public string Name

\[XmlElementAttribute("AreaId", IsNullable = false)\]    // 表现为Xml节点。<AreaId>...</AreaId>  
public string Id

\[XmlArrayAttribute("Areas")\]    // 表现为Xml层次结构，根为Areas，其所属的每个该集合节点元素名为类名。<Areas><Area ... /><Area ... /></Areas>  
public Area\[\] Areas

\[XmlElementAttribute("Area", IsNullable = false)\]    // 表现为水平结构的Xml节点。<Area ... /><Area ... />...  
public Area\[\] Areas

\[XmlIgnoreAttribute\]    // 忽略该元素的序列化。

把这些属性与model类的相关属性，配合使用，就可以自由设置相关XML的具体格式了。

**综合示例：将班级信息序列化成XML**

示例要求：

（1）每个XML节点以“My”开头。

（2）班级ID和学生ID字段以XML节点属性表现，其它字段以XML节点的形式表现。

（3）由于学生的邮箱涉及敏感信息，所以不参与序列化。

**2.1 创建班级信息类（ClassInfo.cs）**

using System.Collections.Generic;
    using System.Xml.Serialization;
    
    /// <summary>
    /// 班级信息类
    /// </summary>
    [XmlRootAttribute("MyClassInfo", Namespace = "ABC_123", IsNullable = false)] 
    public class ClassInfo
    {
        /// <summary>
        /// 班级ID
        /// </summary>
        [XmlAttribute("MyClassID")]
        public int ClassID { get; set; }
    
        /// <summary>
        /// 班级名称
        /// </summary>
        [XmlElementAttribute("MyClassName", IsNullable = false)] 
        public string ClassName { get; set; }
    
        /// <summary>
        /// 班长人
        /// </summary>
        [XmlElementAttribute("MyTeacher", IsNullable = false)] 
        public string Teacher { get; set; }
    
        /// <summary>
        /// 学生列表
        /// </summary>
        [XmlArrayAttribute("MyStudents")]  
        public List<Student> StudentList { get; set; }
    }

**2.2 创建学生信息类（Student.cs）**

using System.Xml.Serialization;
    
    /// <summary>
    /// 学生信息类
    /// </summary>
    [XmlRootAttribute("MyStudent", IsNullable = false)] 
    public class Student
    {
        /// <summary>
        /// 学生ID
        /// </summary>
        [XmlAttribute("MyStuID")]
        public int StuID { get; set; }
    
        /// <summary>
        /// 学生名称
        /// </summary>
        [XmlElementAttribute("MyStuName", IsNullable = false)] 
        public string StuName { get; set; }
    
        /// <summary>
        /// 性别
        /// </summary>
        [XmlElementAttribute("MySex", IsNullable = false)] 
        public string Sex { get; set; }
    
        /// <summary>
        /// 邮箱
        /// </summary>
        [XmlIgnoreAttribute] 
        public string Email { get; set; }
    }

**2.3 将班级信息转换成XML**

/// <summary>
    /// 将班级信息转换成XML
    /// </summary>
    public static void ClassInfoToXml()
    {
        //获取班级信息
        ClassInfo classInfo = GetClassInfo();
    
        //将班级信息转换成XML
        string classXml = XmlSerializeHelper.XmlSerialize(classInfo);
    }
    
    /// <summary>
    /// 获取班级信息
    /// </summary>
    public static ClassInfo GetClassInfo()
    {
        //创建班级信息
        ClassInfo classInfo = new ClassInfo();
        classInfo.ClassID = 1;
        classInfo.ClassName = "高一（5）班";
        classInfo.Teacher = "李老师";
    
        //创建学生列表
        List<Student> studentList = new List<Student>();
        studentList.Add(new Student() { StuID = 1, StuName = "张三", Sex = "男", Email = "zhangsan@mail.com" });
        studentList.Add(new Student() { StuID = 2, StuName = "李四", Sex = "女", Email = "lisi@mail.com" });
        studentList.Add(new Student() { StuID = 3, StuName = "王五", Sex = "男", Email = "wangwu@mail.com" });
        classInfo.StudentList = studentList;
    
        return classInfo;
    }

XML结果：

<?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>李老师</MyTeacher>
      <MyStudents>
        <Student MyStuID="1">
          <MyStuName>张三</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>