本文讲解C#使用XmlEDocument来实现象QQ记录登录过用户名、密码等信息的安全性。类似QQ登录窗口的帐号输入框，这种数据的本地存储
可以把要考虑安全性因素的信息以XML的格式写入内存流中（因为XML操作非常方便），再把整个内存流中加密，保 存成文件（扩展名就无谓了，可以不用.xml，你可以用.dat、.db显得专业点，哈哈）。想到这里，就开始动手，为了提高代码的重用率，把XmlDocument自己封装一下，取名XmlEDocument。代码如下： Code [http://www.xueit.com] 1 using System.Collections.Generic; 2 using System.IO; 3 using System.Security.Cryptography; 4 using System.Text; 5 using System.Xml; 6 7 namespace DotNet.Common 8 { 9 public class XmlEDocument : XmlDocument10 {11 private const string ENCR_KEY = "zhuxiaoc";12 private const int READ_SIZE = 16*1024;13 14 public override void Load(string filename)15 {16 var fileStream = new FileStream(filename, FileMode.Open);17 Load(fileStream);18 }19 20 public override void Load(Stream inStream)21 {22 var bsXml = new List<byte>();23 var b = new byte[READ_SIZE];24 int iLength;25 while ((iLength = inStream.Read(b, 0, READ_SIZE)) > 0)26 {27 for (int i = 0; i < iLength; i )28 {29 bsXml.Add(b[i]);30 }31 }32 inStream.Close();33 var msEXml = new MemoryStream();34 var des = new DESCryptoServiceProvider();35 byte[] byKey = Encoding.UTF8.GetBytes(ENCR_KEY.Substring(0, 8));36 byte[] IV = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF};37 var cs = new CryptoStream(msEXml, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);38 cs.Write(bsXml.ToArray(), 0, bsXml.ToArray().Length);39 cs.FlushFinalBlock();40 base.Load(new MemoryStream(msEXml.ToArray()));41 }42 43 public override void Save(string filename)44 {45 if(!File.Exists(filename))46 File.Create(filename).Close();47 48 var fileStream = new FileStream(filename, FileMode.Truncate);49 Save(fileStream);50 fileStream.Close();51 }52 53 public override void Save(Stream outStream)54 {55 var msXml = new MemoryStream();56 base.Save(msXml);57 var des = new DESCryptoServiceProvider();58 byte[] byKey = Encoding.UTF8.GetBytes(ENCR_KEY.Substring(0, 8));59 byte[] IV = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF};60 var cs = new CryptoStream(outStream, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);61 cs.Write(msXml.ToArray(), 0, msXml.ToArray().Length);62 cs.FlushFinalBlock();63 msXml.Close();64 }65 }66 }写个简单的例子吧：
这是创建XML Code [http://www.xueit.com]1 var xmlDocument = new XmlDocument();2 var dec = xmlDocument.CreateXmlDeclaration("1.0", "utf-8", null);3 xmlDocument.AppendChild(dec);4 var root = xmlDocument.CreateElement("Users");5 xmlDocument.AppendChild(root);6 xmlDocument.Save("c://test.xml");这是创建加密的XML Code [http://www.xueit.com]1 var xmlEDocument = new XmlEDocument();2 var dec = xmlEDocument.CreateXmlDeclaration("1.0", "utf-8", null);3 xmlEDocument.AppendChild(dec);4 var root = xmlEDocument.CreateElement("Users");5 xmlEDocument.AppendChild(root);6 xmlEDocument.Save("c://test.dat");
代码写法完全一样，达到效果确是完全不同。
转载于:https://www.cnblogs.com/deepwishly/archive/2010/09/08/2551201.html
