encryption.cs

提供服务端登陆验证程序（验证码随机改变

using System;
using System.IO;
using System.Security.Cryptography;

namespace MDIServer
{
	/// <summary>
	/// Summary description for Encryption.
	/// </summary>
	public class Encryption
	{
		public Encryption()
		{
		}
		#region encry region
		private HashAlgorithm SetHash()
		{
			return new SHA1CryptoServiceProvider();			
		}

		public string HashString(string Value)
		{
			HashAlgorithm mhash = SetHash();

			// 将原始字符串转换成字节数组
			byte[] bytValue = System.Text.Encoding.UTF8.GetBytes(Value);

			// 计算散列，并返回一个字节数组
			byte[] bytHash = mhash.ComputeHash(bytValue);

			mhash.Clear();

			// 返回散列值的 Base64 编码字符串
			return Convert.ToBase64String(bytHash);
		}
		
		private string GetSalt()
		{
			System.IO.StreamReader saltReader = new StreamReader(@"2046.dat",System.Text.Encoding.UTF8);
			string originalSalt = saltReader.ReadToEnd();
			originalSalt = originalSalt + this.HashString(originalSalt);
			return HashString(originalSalt);
		}

		public string EncrypUser(string userName)
		{
			string saltedValue = GetSalt();
			return this.HashString(userName + saltedValue);
		}
		#endregion
	}
}