在.NET项目中，我们较多的使用到加密这个操作。因为在现代的项目中，对信息安全的要求越来越高，那么多信息的加密就变得至关重要。现在提供几种常用的加密/解密算法。
1.用于文本和Base64编码文本的互相转换 和 Byte[]和Base64编码文本的互相转换：
(1).将普通文本转换成Base64编码的文本
/// <summary>
/// 将普通文本转换成Base64编码的文本 /// </summary>
/// <param name="value">普通文本</param>
/// <returns></returns>
public static string StringToBase64String(string value)
{ if (string.IsNullOrEmpty(value))
{ throw new ArgumentNullException(value);
} try
{ var binBuffer = (new UnicodeEncoding()).GetBytes(value); var base64ArraySize = (int)Math.Ceiling(binBuffer.Length / 3d) * 4; var charBuffer = new char[base64ArraySize];
Convert.ToBase64CharArray(binBuffer, 0, binBuffer.Length, charBuffer, 0); var s = new string(charBuffer); return s;
} catch (Exception ex)
{ throw new Exception(ex.Message);
}
}
(2).将Base64编码的文本转换成普通文本
/// <summary>
/// 将Base64编码的文本转换成普通文本 /// </summary>
/// <param name="base64">Base64编码的文本</param>
/// <returns></returns>
public static string Base64StringToString(string base64)
{ if (string.IsNullOrEmpty(base64))
{ throw new ArgumentNullException(base64);
} try
{ var charBuffer = base64.ToCharArray(); var bytes = Convert.FromBase64CharArray(charBuffer, 0, charBuffer.Length); return (new UnicodeEncoding()).GetString(bytes);
} catch (Exception ex)
{ throw new Exception(ex.Message);
}
}
(3).将Byte[]转换成Base64编码文本
/// <summary>
/// 将Byte[]转换成Base64编码文本 /// </summary>
/// <param name="binBuffer">Byte[]</param>
/// <returns></returns>
public string ToBase64(byte[] binBuffer)
{ if (binBuffer == null)
{ throw new ArgumentNullException("binBuffer");
} try
{ var base64ArraySize = (int)Math.Ceiling(binBuffer.Length / 3d) * 4; var charBuffer = new char[base64ArraySize];
Convert.ToBase64CharArray(binBuffer, 0, binBuffer.Length, charBuffer, 0); var s = new string(charBuffer); return s;
} catch (Exception ex)
{ throw new Exception(ex.Message);
}
}
(4).将Base64编码文本转换成Byte[]
/// <summary>
/// 将Base64编码文本转换成Byte[] /// </summary>
/// <param name="base64">Base64编码文本</param>
/// <returns></returns>
public byte[] Base64ToBytes(string base64)
{ if (string.IsNullOrEmpty(base64))
{ throw new ArgumentNullException(base64);
} try
{ var charBuffer = base64.ToCharArray(); var bytes = Convert.FromBase64CharArray(charBuffer, 0, charBuffer.Length); return bytes;
} catch (Exception ex)
{ throw new Exception(ex.Message);
}
}
2. DES加密/解密类。
(1).加密
private static readonly string KEY = "pengze0902"; /// <summary>
/// 加密 /// </summary>
/// <param name="Text"></param>
/// <returns></returns>
public static string Encrypt(string Text)
{ return Encrypt(Text, KEY);
} /// <summary>
/// 加密数据
/// </summary>
/// <param name="Text"></param>
/// <param name="sKey"></param>
/// <returns></returns>
public static string Encrypt(string Text, string sKey)
{ var des = new DESCryptoServiceProvider(); var inputByteArray = Encoding.Default.GetBytes(Text); var bKey = Encoding.ASCII.GetBytes(Md5Hash(sKey).Substring(0, 8));
des.Key = bKey;
des.IV = bKey; var ms = new System.IO.MemoryStream(); var cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock(); var ret = new StringBuilder(); foreach (byte b in ms.ToArray())
{
ret.AppendFormat("{0:X2}", b);
} return ret.ToString();
}
(2).解密
private static readonly string KEY = "pengze0902"; /// <summary>
/// 解密 /// </summary>
/// <param name="text"></param>
/// <returns></returns>
public static string Decrypt(string text)
{ return Decrypt(text, KEY);
} /// <summary>
/// 解密数据
/// </summary>
/// <param name="text"></param>
/// <param name="sKey"></param>
/// <returns></returns>
public static string Decrypt(string text, string sKey)
{ var des = new DESCryptoServiceProvider(); var len = text.Length / 2; byte[] inputByteArray = new byte[len]; int x; for (x = 0; x < len; x++)
{ var i = Convert.ToInt32(text.Substring(x * 2, 2), 16);
inputByteArray[x] = (byte)i;
} var bKey = Encoding.ASCII.GetBytes(Md5Hash(sKey).Substring(0, 8));
des.Key = bKey;
des.IV = bKey;
System.IO.MemoryStream ms = new System.IO.MemoryStream();
CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock(); return Encoding.Default.GetString(ms.ToArray());
}
(3).取得MD5加密串
//// <summary>
/// 取得MD5加密串 /// </summary>
/// <param name="input">源明文字符串</param>
/// <returns>密文字符串</returns>
public static string Md5Hash(string input)
{ var md5 = new MD5CryptoServiceProvider(); var bs = Encoding.UTF8.GetBytes(input);
bs = md5.ComputeHash(bs); var s = new StringBuilder(); foreach (var b in bs)
{
s.Append(b.ToString("x2").ToUpper());
} var password = s.ToString(); return password;
}
3.MD5加密
(1). 32位大写
/// <summary>
/// 32位大写 /// </summary>
/// <returns></returns>
public static string Upper32(string s)
{ var hashPasswordForStoringInConfigFile = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(s, "md5"); if (hashPasswordForStoringInConfigFile != null)
s = hashPasswordForStoringInConfigFile.ToString(); return s.ToUpper();
}
(2). 32位小写
/// <summary>
/// 32位小写 /// </summary>
/// <returns></returns>
public static string Lower32(string s)
{ var hashPasswordForStoringInConfigFile = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(s, "md5"); if (hashPasswordForStoringInConfigFile != null)
s = hashPasswordForStoringInConfigFile.ToString(); return s.ToLower();
}
(3).16位大写
/// <summary>
/// 16位大写 /// </summary>
/// <returns></returns>
public static string Upper16(string s)
{ var hashPasswordForStoringInConfigFile = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(s, "md5"); if (hashPasswordForStoringInConfigFile != null)
s = hashPasswordForStoringInConfigFile.ToString(); return s.ToUpper().Substring(8, 16);
}
(4).16位小写
/// <summary>
/// 16位小写 /// </summary>
/// <returns></returns>
public static string Lower16(string s)
{ var hashPasswordForStoringInConfigFile = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(s, "md5"); if (hashPasswordForStoringInConfigFile != null)
s = hashPasswordForStoringInConfigFile.ToString(); return s.ToLower().Substring(8, 16);
}
4.Sha1签名算法
/// <summary>
/// 签名算法 /// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string GetSha1(string str)
{ if (string.IsNullOrEmpty(str))
{ throw new ArgumentNullException(str);
} try
{ //建立SHA1对象
SHA1 sha = new SHA1CryptoServiceProvider(); //将mystr转换成byte[]
var enc = new ASCIIEncoding(); var dataToHash = enc.GetBytes(str); //Hash运算
var dataHashed = sha.ComputeHash(dataToHash); //将运算结果转换成string
var hash = BitConverter.ToString(dataHashed).Replace("-", ""); return hash;
} catch (Exception ex)
{ throw new Exception(ex.Message);
}
}
5.Sha256加密算法
/// <summary>
/// 将字符串转换为sha256散列 /// </summary>
/// <param name="data">字符串进行转换</param>
/// <returns>sha256散列或null</returns>
public static string ToSha256(this string data)
{ try
{ if (string.IsNullOrEmpty(data)) return null; var hashValue = new SHA256Managed().ComputeHash(Encoding.UTF8.GetBytes(data)); var hex = hashValue.Aggregate("", (current, x) => current + String.Format("{0:x2}", x)); if (string.IsNullOrEmpty(hex)) throw new Exception("Erro creating SHA256 hash"); return hex;
} catch (Exception e)
{ throw new Exception(e.Message, e);
}
}
以上是一些较为常用的算法代码。
原文地址：http://zhangtaoze.blog.51cto.com/12776936/1913403
