C# Note4:XML序列化和反序列化（含加密解密等）

前言

       在项目中，我们经常用到各种配置文件，比如xml文件、binary文件等等，这里主要根据实践经验介绍下xml文件的序列化和反序列化（毕竟最常用）。

实践背景：我要做一个用户管理功能，用户账号信息存储在xml/binary文件中，需要对其进行读写，而且为了不让用户修改，必须对其加密，当时想的有3种做法：

（1）实现读写xml配置文件，并将关键信息加密；

（2）实现读写binary配置文件，并将关键信息加密；

（3）直接对配置文件进行加密解密和读写，不管它所使用的文件格式是xml、binary或其它。

这三种做法我都实现了，不过经过最后manager的确认觉得采用第（3）种方法最好。

方法一：

（推荐：Load and save objects to XML using serialization  本方法参考其思路）

（1）在我们将对象序列化为XML之前，对象的类代码必须包含各种自定义元数据属性(例如，[XmlAttributeAttribute(DataType = " date "])告诉编译器类及其字段和/或属性可以被序列化。

using System;
using System.Xml.Serialization;
using System.Collections.ObjectModel;

namespace XXX.GlobalTypes
{
    /// <summary>
    /// Save user account information
    /// </summary>
    [Serializable]
    [XmlRoot("UserManagement")]
    public class UserAccountInfo
    {
        private readonly Collection<UserInfo> _users = new Collection<UserInfo>();

        [XmlElement("UserAccountInfo")]
        public Collection<UserInfo> Users
        {
            get { return this._users; }
        }
    }

    [Serializable]
    public class UserInfo
    {

        [XmlElement("UserName")]
        public string UserName
        {
            get;
            set;
        }

        [XmlElement("UserPwd")]
        public string UserPwd
        {
            get;
            set;
        }

        [XmlElement("UserRole")]
        public ACCESS_LEVEL UserRole
        {
            get;
            set;
        }

        [XmlElement("Description")]
        public string Description
        {
            get;
            set;
        }
    }

}

（2）封装XML序列化的类（其中作为样例，我加入了加密解密的参数tDESkey，在将数据对象保存到xml文件后进行加密，从xml文件中读取数据前先进行解密）：

using System;
using System.Xml;
using System.Security.Cryptography;
using System.Security.Cryptography.Xml;
using System.Xml.Serialization;     // For serialization of an object to an XML Document file.
using System.Runtime.Serialization.Formatters.Binary; // For serialization of an object to an XML Binary file.
using System.IO;                 // For reading/writing data to an XML file.
using System.IO.IsolatedStorage; // For accessing user isolated data.

namespace XXX.Utilities.Common
{
    /// <summary>
    /// Serialization format types.
    /// </summary>
    public enum SerializedFormat
    {
        /// <summary>
        /// Binary serialization format.
        /// </summary>
        Binary,

        /// <summary>
        /// Document serialization format.
        /// </summary>
        Document
    }


    /// <summary>
    /// Facade to XML serialization and deserialization of strongly typed objects to/from an XML file.
    /// 
    /// References: XML Serialization at http://samples.gotdotnet.com/:
    /// http://samples.gotdotnet.com/QuickStart/howto/default.aspx?url=/quickstart/howto/doc/xmlserialization/rwobjfromxml.aspx
    /// </summary>
    public static class ObjectXMLSerializer<T> where T : class // Specify that T must be a class.
    {
        #region Load methods

        /// <summary>
        /// Loads an object from an XML file in Document format.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load(@"C:XMLObjects.xml");
        /// </code>
        /// </example>
        /// <param name="path">Path of the file to load the object from.</param>
        /// <returns>Object loaded from an XML file in Document format.</returns>
        public static T Load(string path, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = LoadFromDocumentFormat(null, path, null, tDESkey);
            return serializableObject;
        }

        /// <summary>
        /// Loads an object from an XML file using a specified serialized format.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load(@"C:XMLObjects.xml", SerializedFormat.Binary);
        /// </code>
        /// </example>        
        /// <param name="path">Path of the file to load the object from.</param>
        /// <param name="serializedFormat">XML serialized format used to load the object.</param>
        /// <returns>Object loaded from an XML file using the specified serialized format.</returns>
        public static T Load(string path, SerializedFormat serializedFormat, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = null;

            switch (serializedFormat)
            {
                case SerializedFormat.Binary:
                    serializableObject = LoadFromBinaryFormat(path, null);
                    break;

                case SerializedFormat.Document:
                default:
                    serializableObject = LoadFromDocumentFormat(null, path, null, tDESkey);
                    break;
            }

            return serializableObject;
        }

        /// <summary>
        /// Loads an object from an XML file in Document format, supplying extra data types to enable deserialization of custom types within the object.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load(@"C:XMLObjects.xml", new Type[] { typeof(MyCustomType) });
        /// </code>
        /// </example>
        /// <param name="path">Path of the file to load the object from.</param>
        /// <param name="extraTypes">Extra data types to enable deserialization of custom types within the object.</param>
        /// <returns>Object loaded from an XML file in Document format.</returns>
        public static T Load(string path, System.Type[] extraTypes, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = LoadFromDocumentFormat(extraTypes, path, null, tDESkey);
            return serializableObject;
        }

        /// <summary>
        /// Loads an object from an XML file in Document format, located in a specified isolated storage area.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load("XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly());
        /// </code>
        /// </example>
        /// <param name="fileName">Name of the file in the isolated storage area to load the object from.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to load the object from.</param>
        /// <returns>Object loaded from an XML file in Document format located in a specified isolated storage area.</returns>
        public static T Load(string fileName, IsolatedStorageFile isolatedStorageDirectory, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = LoadFromDocumentFormat(null, fileName, isolatedStorageDirectory, tDESkey);
            return serializableObject;
        }

        /// <summary>
        /// Loads an object from an XML file located in a specified isolated storage area, using a specified serialized format.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load("XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly(), SerializedFormat.Binary);
        /// </code>
        /// </example>        
        /// <param name="fileName">Name of the file in the isolated storage area to load the object from.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to load the object from.</param>
        /// <param name="serializedFormat">XML serialized format used to load the object.</param>        
        /// <returns>Object loaded from an XML file located in a specified isolated storage area, using a specified serialized format.</returns>
        public static T Load(string fileName, IsolatedStorageFile isolatedStorageDirectory, SerializedFormat serializedFormat, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = null;

            switch (serializedFormat)
            {
                case SerializedFormat.Binary:
                    serializableObject = LoadFromBinaryFormat(fileName, isolatedStorageDirectory);
                    break;

                case SerializedFormat.Document:
                default:
                    serializableObject = LoadFromDocumentFormat(null, fileName, isolatedStorageDirectory, tDESkey);
                    break;
            }

            return serializableObject;
        }

        /// <summary>
        /// Loads an object from an XML file in Document format, located in a specified isolated storage area, and supplying extra data types to enable deserialization of custom types within the object.
        /// </summary>
        /// <example>
        /// <code>
        /// serializableObject = ObjectXMLSerializer&lt;SerializableObject&gt;.Load("XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly(), new Type[] { typeof(MyCustomType) });
        /// </code>
        /// </example>        
        /// <param name="fileName">Name of the file in the isolated storage area to load the object from.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to load the object from.</param>
        /// <param name="extraTypes">Extra data types to enable deserialization of custom types within the object.</param>
        /// <returns>Object loaded from an XML file located in a specified isolated storage area, using a specified serialized format.</returns>
        public static T Load(string fileName, IsolatedStorageFile isolatedStorageDirectory, System.Type[] extraTypes, TripleDESCryptoServiceProvider tDESkey)
        {
            T serializableObject = LoadFromDocumentFormat(null, fileName, isolatedStorageDirectory, tDESkey);
            return serializableObject;
        }

        #endregion

        #region Save methods

        /// <summary>
        /// Saves an object to an XML file in Document format.
        /// </summary>
        /// <example>
        /// <code>        
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, @"C:XMLObjects.xml");
        /// </code>
        /// </example>
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="path">Path of the file to save the object to.</param>
        public static void Save(T serializableObject, string path, TripleDESCryptoServiceProvider tDESkey)
        {
            SaveToDocumentFormat(serializableObject, null, path, null, tDESkey);
        }

        /// <summary>
        /// Saves an object to an XML file using a specified serialized format.
        /// </summary>
        /// <example>
        /// <code>
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, @"C:XMLObjects.xml", SerializedFormat.Binary);
        /// </code>
        /// </example>
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="path">Path of the file to save the object to.</param>
        /// <param name="serializedFormat">XML serialized format used to save the object.</param>
        public static void Save(T serializableObject, string path, SerializedFormat serializedFormat, TripleDESCryptoServiceProvider tDESkey)
        {
            switch (serializedFormat)
            {
                case SerializedFormat.Binary:
                    SaveToBinaryFormat(serializableObject, path, null);
                    break;

                case SerializedFormat.Document:
                default:
                    SaveToDocumentFormat(serializableObject, null, path, null, tDESkey);
                    break;
            }
        }

        /// <summary>
        /// Saves an object to an XML file in Document format, supplying extra data types to enable serialization of custom types within the object.
        /// </summary>
        /// <example>
        /// <code>        
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, @"C:XMLObjects.xml", new Type[] { typeof(MyCustomType) });
        /// </code>
        /// </example>
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="path">Path of the file to save the object to.</param>
        /// <param name="extraTypes">Extra data types to enable serialization of custom types within the object.</param>
        public static void Save(T serializableObject, string path, System.Type[] extraTypes, TripleDESCryptoServiceProvider tDESkey)
        {
            SaveToDocumentFormat(serializableObject, extraTypes, path, null, tDESkey);
        }

        /// <summary>
        /// Saves an object to an XML file in Document format, located in a specified isolated storage area.
        /// </summary>
        /// <example>
        /// <code>        
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, "XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly());
        /// </code>
        /// </example>
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="fileName">Name of the file in the isolated storage area to save the object to.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to save the object to.</param>
        public static void Save(T serializableObject, string fileName, IsolatedStorageFile isolatedStorageDirectory, TripleDESCryptoServiceProvider tDESkey)
        {
            SaveToDocumentFormat(serializableObject, null, fileName, isolatedStorageDirectory, tDESkey);
        }

        /// <summary>
        /// Saves an object to an XML file located in a specified isolated storage area, using a specified serialized format.
        /// </summary>
        /// <example>
        /// <code>        
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, "XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly(), SerializedFormat.Binary);
        /// </code>
        /// </example>
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="fileName">Name of the file in the isolated storage area to save the object to.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to save the object to.</param>
        /// <param name="serializedFormat">XML serialized format used to save the object.</param>        
        public static void Save(T serializableObject, string fileName, IsolatedStorageFile isolatedStorageDirectory, SerializedFormat serializedFormat, TripleDESCryptoServiceProvider tDESkey)
        {
            switch (serializedFormat)
            {
                case SerializedFormat.Binary:
                    SaveToBinaryFormat(serializableObject, fileName, isolatedStorageDirectory);
                    break;

                case SerializedFormat.Document:
                default:
                    SaveToDocumentFormat(serializableObject, null, fileName, isolatedStorageDirectory, tDESkey);
                    break;
            }
        }

        /// <summary>
        /// Saves an object to an XML file in Document format, located in a specified isolated storage area, and supplying extra data types to enable serialization of custom types within the object.
        /// </summary>
        /// <example>
        /// <code>
        /// SerializableObject serializableObject = new SerializableObject();
        /// 
        /// ObjectXMLSerializer&lt;SerializableObject&gt;.Save(serializableObject, "XMLObjects.xml", IsolatedStorageFile.GetUserStoreForAssembly(), new Type[] { typeof(MyCustomType) });
        /// </code>
        /// </example>        
        /// <param name="serializableObject">Serializable object to be saved to file.</param>
        /// <param name="fileName">Name of the file in the isolated storage area to save the object to.</param>
        /// <param name="isolatedStorageDirectory">Isolated storage area directory containing the XML file to save the object to.</param>
        /// <param name="extraTypes">Extra data types to enable serialization of custom types within the object.</param>
        public static void Save(T serializableObject, string fileName, IsolatedStorageFile isolatedStorageDirectory, System.Type[] extraTypes, TripleDESCryptoServiceProvider tDESkey)
        {
            SaveToDocumentFormat(serializableObject, null, fileName, isolatedStorageDirectory, tDESkey);
        }

        #endregion

        #region Private

        private static FileStream CreateFileStream(IsolatedStorageFile isolatedStorageFolder, string path)
        {
            FileStream fileStream = null;

            if (isolatedStorageFolder == null)
                fileStream = new FileStream(path, FileMode.OpenOrCreate);
            else
                fileStream = new IsolatedStorageFileStream(path, FileMode.OpenOrCreate, isolatedStorageFolder);

            return fileStream;
        }

        private static T LoadFromBinaryFormat(string path, IsolatedStorageFile isolatedStorageFolder)
        {
            T serializableObject = null;

            using (FileStream fileStream = CreateFileStream(isolatedStorageFolder, path))
            {
                BinaryFormatter binaryFormatter = new BinaryFormatter();
                serializableObject = binaryFormatter.Deserialize(fileStream) as T;
            }

            return serializableObject;
        }

        private static T LoadFromDocumentFormat(System.Type[] extraTypes, string path, IsolatedStorageFile isolatedStorageFolder, TripleDESCryptoServiceProvider tDESkey)
        {
            XmlDocument xmlDoc = new XmlDocument();
            try
            {
                xmlDoc.PreserveWhitespace = true;

                xmlDoc.Load(path);
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }

            // Decrypt the "UserManagement" element.
            EncryptXml.Decrypt(xmlDoc, tDESkey);
            xmlDoc.Save(path);

            T serializableObject = null;

            using (TextReader textReader = CreateTextReader(isolatedStorageFolder, path))
            {
                XmlSerializer xmlSerializer = CreateXmlSerializer(extraTypes);
                serializableObject = xmlSerializer.Deserialize(textReader) as T;
            }

            EncryptXml.Encrypt(xmlDoc, "UserManagement", tDESkey);
            xmlDoc.Save(path);

            return serializableObject;
        }

        private static TextReader CreateTextReader(IsolatedStorageFile isolatedStorageFolder, string path)
        {
            TextReader textReader = null;

            if (isolatedStorageFolder == null)
                textReader = new StreamReader(path);
            else
                textReader = new StreamReader(new IsolatedStorageFileStream(path, FileMode.Open, isolatedStorageFolder));

            return textReader;
        }

        private static TextWriter CreateTextWriter(IsolatedStorageFile isolatedStorageFolder, string path)
        {
            TextWriter textWriter = null;

            if (isolatedStorageFolder == null)
                textWriter = new StreamWriter(path);
            else
                textWriter = new StreamWriter(new IsolatedStorageFileStream(path, FileMode.OpenOrCreate, isolatedStorageFolder));

            return textWriter;
        }

        private static XmlSerializer CreateXmlSerializer(System.Type[] extraTypes)
        {
            Type ObjectType = typeof(T);

            XmlSerializer xmlSerializer = null;

            if (extraTypes != null)
                xmlSerializer = new XmlSerializer(ObjectType, extraTypes);
            else
                xmlSerializer = new XmlSerializer(ObjectType);

            return xmlSerializer;
        }

        private static void SaveToDocumentFormat(T serializableObject, System.Type[] extraTypes, string path, IsolatedStorageFile isolatedStorageFolder, TripleDESCryptoServiceProvider tDESkey)
        {
            using (TextWriter textWriter = CreateTextWriter(isolatedStorageFolder, path))
            {
                XmlSerializer xmlSerializer = CreateXmlSerializer(extraTypes);
                xmlSerializer.Serialize(textWriter, serializableObject);

                textWriter.Close();

                XmlDocument xmlDoc = new XmlDocument();
                try
                {
                    xmlDoc.PreserveWhitespace = true;

                    xmlDoc.Load(path);
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.Message);
                }

                EncryptXml.Encrypt(xmlDoc, "UserManagement", tDESkey);

                xmlDoc.Save(path);
            }
        }

        private static void SaveToBinaryFormat(T serializableObject, string path, IsolatedStorageFile isolatedStorageFolder)
        {
            using (FileStream fileStream = CreateFileStream(isolatedStorageFolder, path))
            {
                BinaryFormatter binaryFormatter = new BinaryFormatter();
                binaryFormatter.Serialize(fileStream, serializableObject);
            }
        }

        
        #endregion
    }
}

（3）Saving an object to an XML file/Loading an object from an XML file

// Load the userManagement object from the XML file using our UserAccountInfo class...
UserAccountInfo userManagement =ObjectXMLSerializer<UserAccountInfo>.Load(path, tDESkey);

// Load the userManagement object from the XML file using our userManagement class...
ObjectXMLSerializer<UserAccountInfo>.Save(usermanagement, XML_FILE_NAME, tDESkey);

方法二：

其实，要想仅仅实现xml的序列化和反序列化还是很简单的，作为常用的类，可以很简单地将其实现为公共类：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml;
using System.Xml.Serialization;

namespace XXX.Common
{
    public static class XmlHelper
    {
        public static object DeserializeObject<T>(string filePath)
        {
            try
            {
                var xs = new XmlSerializer(typeof(T));
                using (var fs = new FileStream(filePath, FileMode.Open))
                {
                    var reader = XmlReader.Create(fs);
                    return xs.Deserialize(reader);
                }
            }
            catch (Exception exp)
            {
                throw new XmlException($"Failed in XML Deserialization {filePath}", exp);
            }
        }

        public static void SerializeObject<T>(string filePath, T o)
        {
            try
            {
                var x = new XmlSerializer(typeof(T));
                using (var fs = new FileStream(filePath, FileMode.Create))
                {
                    var writer = XmlWriter.Create(fs);
                    x.Serialize(writer, o);
                }
            }
            catch (Exception exp)
            {
                throw new XmlException($"Failed in XML Serialization {filePath}", exp);
            }
        }
    }
}

　　

　

另可参考文章：

1.XML序列化和反序列化

2.在.net中读写config文件的各种方法