C#实现Base64加密解密

方法一

class Base64Helper
{
/// <summary>
/// Base64加密，采用utf8编码方式加密
/// </summary>
/// <param name="source">待加密的明文</param>
/// <returns>加密后的字符串</returns>
public static string Base64Encode(string source)
{
return Base64Encode(Encoding.UTF8, source);
}

/// <summary>
/// Base64加密
/// </summary>
/// <param name="encodeType">加密采用的编码方式</param>
/// <param name="source">待加密的明文</param>
/// <returns></returns>
public static string Base64Encode(Encoding encodeType, string source)
{
string encode = string.Empty;
byte[] bytes = encodeType.GetBytes(source);
try
{
encode = Convert.ToBase64String(bytes);
}
catch
{
encode = source;
}
return encode;
}

/// <summary>
/// Base64解密，采用utf8编码方式解密
/// </summary>
/// <param name="result">待解密的密文</param>
/// <returns>解密后的字符串</returns>
public static string Base64Decode(string result)
{
return Base64Decode(Encoding.UTF8, result);
}

/// <summary>
/// Base64解密
/// </summary>
/// <param name="encodeType">解密采用的编码方式，注意和加密时采用的方式一致</param>
/// <param name="result">待解密的密文</param>
/// <returns>解密后的字符串</returns>
public static string Base64Decode(Encoding encodeType, string result)
{
string decode = string.Empty;
byte[] bytes = Convert.FromBase64String(result);
try
{
decode = encodeType.GetString(bytes);
}
catch
{
decode = result;
}
return decode;
}
}

方法二

class Program
{
static void Main(string[] args)
{
string original = "123456";

var md5 = BitConverter.ToString(new System.Security.Cryptography.MD5CryptoServiceProvider().ComputeHash(Encoding.Default.GetBytes(original))).Replace("-", "").ToLower();
Console.WriteLine("md5=" + md5);

//b64是以=结尾的长度为24位的密文
var b64 = Convert.ToBase64String(new System.Security.Cryptography.MD5CryptoServiceProvider().ComputeHash(Encoding.Default.GetBytes(original)));
Console.WriteLine("b64=" + b64);

var dec = BitConverter.ToString(new System.Security.Cryptography.FromBase64Transform().TransformFinalBlock(Encoding.Default.GetBytes(b64), 0, Encoding.Default.GetBytes(b64).Length)).Replace("-","").ToLower();
Console.WriteLine("dec=" + dec);
Console.ReadLine();
}
}