在.NET項目中，我們較多的使用到加密這個操作。因為在現代的項目中，對信息安全的要求越來越高，那麼多信息的加密就變得至關重要。現在提供幾種常用的加密/解密算法。
1.用於文本和Base64編碼文本的互相轉換 和 Byte[]和Base64編碼文本的互相轉換：
(1).將普通文本轉換成Base64編碼的文本
/// <summary>
/// 將普通文本轉換成Base64編碼的文本
/// </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).將Base64編碼的文本轉換成普通文本
/// <summary>
/// 將Base64編碼的文本轉換成普通文本
/// </summary>
/// <param name="base64">Base64編碼的文本</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).將Byte[]轉換成Base64編碼文本
/// <summary>
/// 將Byte[]轉換成Base64編碼文本
/// </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).將Base64編碼文本轉換成Byte[]
/// <summary>
/// 將Base64編碼文本轉換成Byte[]
/// </summary>
/// <param name="base64">Base64編碼文本</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/解密類。
(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>
/// 加密數據
/// </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>
/// 解密數據
/// </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位大寫
/// <summary>
/// 32位大寫
/// </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位小寫
/// <summary>
/// 32位小寫
/// </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位大寫
/// <summary>
/// 16位大寫
/// </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位小寫
/// <summary>
/// 16位小寫
/// </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簽名算法
/// <summary>
/// 簽名算法
/// </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對象
SHA1 sha = new SHA1CryptoServiceProvider();
//將mystr轉換成byte[]
var enc = new ASCIIEncoding();
var dataToHash = enc.GetBytes(str);
//Hash運算
var dataHashed = sha.ComputeHash(dataToHash);
//將運算結果轉換成string
var hash = BitConverter.ToString(dataHashed).Replace("-", "");
return hash;
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
5.Sha256加密算法
/// <summary>
/// 將字符串轉換為sha256散列
/// </summary>
/// <param name="data">字符串進行轉換</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);
}
}
以上是一些較為常用的算法代碼。
