Asp. NET encryption and decryption algorithm sharing _ practical skills

#region des encryption and decryption///<summary>///des encryption///</summary>///<param name= "strsource" > Pending encrypted Word Strings </param>///<param name= "key" >32 bit key value </param>///<returns> encrypted string </returns> p
    Ublic string Desencrypt (String strsource) {return desencrypt (strsource, Deskey);
      public string Desencrypt (String strsource, byte[] key) {symmetricalgorithm sa = rijndael.create (); Sa.
      key = key; Sa.
      Mode = CIPHERMODE.ECB; Sa.
      Padding = Paddingmode.zeros;
      MemoryStream ms = new MemoryStream (); CryptoStream cs = new CryptoStream (MS, SA.
      CreateEncryptor (), cryptostreammode.write);
      byte[] byt = Encoding.Unicode.GetBytes (strsource); Cs. Write (byt, 0, Byt.
      Length); Cs.
      FlushFinalBlock (); Cs.
      Close (); Return convert.tobase64string (Ms.
    ToArray ()); ///<summary>///des decryption///</summary>///<param name= "strsource" > Strings to be decrypted </param&gt
;    <param name= "key" >32 bit key value </param>///<returns> decrypted string </returns> public string DES
    Decrypt (String strsource) {return desdecrypt (strsource, Deskey);
      public string Desdecrypt (String strsource, byte[] key) {symmetricalgorithm sa = rijndael.create (); Sa.
      key = key; Sa.
      Mode = CIPHERMODE.ECB; Sa.
      Padding = Paddingmode.zeros; ICryptoTransform ct = sa.
      CreateDecryptor ();
      byte[] byt = convert.frombase64string (strsource);
      MemoryStream ms = new MemoryStream (byt);
      CryptoStream cs = new CryptoStream (MS, CT, cryptostreammode.read);
      StreamReader sr = new StreamReader (cs, Encoding.unicode); return Sr.
    ReadToEnd (); #endregion #region A hash-implemented cryptographic decryption method///<summary>///encryption///</summary>///<para M name= "src" ></param>///<returns></returns> public static string Encryptstrbyhash (String sr c) {if (src). LeNgth = = 0) {return ""; } byte[] Hakey = System.Text.Encoding.ASCII.GetBytes (src + "Test").
      ToCharArray ());
      byte[] Hadata = new BYTE[20];
      HMACSHA1 Hmac = new HMACSHA1 (Hakey);
      CryptoStream cs = new CryptoStream (Stream.null, Hmac, CryptoStreamMode.Write); try {cs.
      Write (hadata, 0, hadata.length); finally {cs.
      Close (); String haresult = System.Convert.ToBase64String (Hmac.hash).
      Substring (0, 16);
      byte[] Rikey = System.Text.Encoding.ASCII.GetBytes (Haresult.tochararray ()); byte[] ridatabuf = System.Text.Encoding.ASCII.GetBytes (src.
      ToCharArray ());
      Byte[] encodedbytes = {};
      MemoryStream ms = new MemoryStream ();
      RijndaelManaged RV = new RijndaelManaged (); CS = new CryptoStream (MS, RV.
      CreateEncryptor (Rikey, Rikey), cryptostreammode.write); try {cs.
        Write (ridatabuf, 0, ridatabuf.length); Cs.
        FlushFinalBlock (); Encodedbytes = Ms.
      ToArray (); finally {Ms.
        Close (); Cs.
      Close ();
    return Haresult + System.Convert.ToBase64String (encodedbytes); ///<summary>///decryption///</summary>///<param name= "src" ></param>///<r eturns></returns> public static string Decrypstrbyhash (String src) {if (src).
      Length <) return ""; byte[] srcbytes = System.Convert.FromBase64String (src.
      Substring (16)); byte[] Rikey = System.Text.Encoding.ASCII.GetBytes (src. Substring (0, 16).
      ToCharArray ());
      byte[] Initialtext = new Byte[srcbytes.length];
      RijndaelManaged RV = new RijndaelManaged ();
      MemoryStream ms = new MemoryStream (srcbytes); CryptoStream cs = new CryptoStream (MS, RV.
      CreateDecryptor (Rikey, Rikey), cryptostreammode.read); try {cs.
      Read (initialtext, 0, initialtext.length); finally {Ms.
        Close (); Cs.
      Close ();
    }  System.Text.StringBuilder result = new System.Text.StringBuilder ();
      for (int i = 0; i < initialtext.length ++i) if (Initialtext[i] > 0) result.append ((char) initialtext[i]);
    return result.tostring (); ///<summary>///to encode encrypted ciphertext, if the cipher is long >16, remove the first 16 characters, if the length is less than 16, return an empty string///</summary>///<p
    Aram Name= "s" ></param>///<returns></returns> public string Reencryptstrbyhash (string s)
      {String E = Encrypt.encryptstrbyhash (s);
    Return ((E.length >) e.substring (16): ""); #endregion #region MD5 Encryption, generates 16-bit or 32-bit, generated ciphertext is all uppercase public static string md5to16 (String str) {Md5cryptos
      Erviceprovider MD5 = new MD5CryptoServiceProvider ();
      String t2 = bitconverter.tostring (Md5.computehash (UTF8Encoding.Default.GetBytes (str)), 4, 8); t2 = T2.
      Replace ("-", "");
    return T2; }////<summary>///MD5 32-bit encryption///</summary>///<param name="Str" ></param>///<returns></returns> public static string Md5to32 (String str) {s
      Tring pwd = ""; MD5 MD5 = MD5.
      Create ();
      Byte[] s = Md5.computehash (Encoding.UTF8.GetBytes (str)); for (int i = 0; i < s.length i++) {pwd = pwd + s[i].
      ToString ("X");
    return pwd; #endregion #region 3DES Encryption Decryption public string encrypt3des (String str) {//key string SKey = "Wyw3
      08 ";
      Vector, can be empty string SIV = "scf521";
      Constructing symmetric algorithm SymmetricAlgorithm MCSP = new TripleDESCryptoServiceProvider ();
      ICryptoTransform CT;
      MemoryStream MS;
      CryptoStream CS;
      Byte[] byt;
      Mcsp.key = convert.frombase64string (SKey);
      MCSP.IV = convert.frombase64string (SIV);
      Mcsp.mode = System.Security.Cryptography.CipherMode.ECB;
      mcsp.padding = System.Security.Cryptography.PaddingMode.PKCS7;
      ct = Mcsp.createencryptor (Mcsp.key, MCSP.IV); Byt =Encoding.UTF8.GetBytes (str);
      ms = new MemoryStream ();
      CS = new CryptoStream (MS, CT, cryptostreammode.write); Cs. Write (byt, 0, Byt.
      Length); Cs.
      FlushFinalBlock (); Cs.
      Close (); Return convert.tobase64string (Ms.
    ToArray ());
    ///<summary>///3DES encryption///</summary>///<param name= "str" with specified keys and vectors ></param> <param name= "SKey" ></param>///<param name= "SIV" ></param>///<returns>< /returns> public string Encrypt3des (String str, string SKey, String SIV) {SymmetricAlgorithm MCSP = new
      TripleDESCryptoServiceProvider ();
      ICryptoTransform CT;
      MemoryStream MS;
      CryptoStream CS;
      Byte[] byt;
      Mcsp.key = convert.frombase64string (SKey);
      MCSP.IV = convert.frombase64string (SIV);
      Mcsp.mode = System.Security.Cryptography.CipherMode.ECB;
      mcsp.padding = System.Security.Cryptography.PaddingMode.PKCS7; CT = mcsp.createeNcryptor (Mcsp.key, MCSP.IV);
      BYT = Encoding.UTF8.GetBytes (str);
      ms = new MemoryStream ();
      CS = new CryptoStream (MS, CT, cryptostreammode.write); Cs. Write (byt, 0, Byt.
      Length); Cs.
      FlushFinalBlock (); Cs.
      Close (); Return convert.tobase64string (Ms.
    ToArray ());
      //Decrypt public string Decrypt3des (string Value) {string sKey = "wyw308";
      String SIV = "scf521";
      SymmetricAlgorithm MCSP = new TripleDESCryptoServiceProvider ();
      ICryptoTransform CT;
      MemoryStream MS;
      CryptoStream CS;
      Byte[] byt;
      Mcsp.key = convert.frombase64string (SKey);
      MCSP.IV = convert.frombase64string (SIV);
      Mcsp.mode = System.Security.Cryptography.CipherMode.ECB;
      mcsp.padding = System.Security.Cryptography.PaddingMode.PKCS7;
      ct = Mcsp.createdecryptor (Mcsp.key, MCSP.IV);
      Byt = convert.frombase64string (Value);
      ms = new MemoryStream ();
   CS = new CryptoStream (MS, CT, cryptostreammode.write);   Cs. Write (byt, 0, Byt.
      Length); Cs.
      FlushFinalBlock (); Cs.
      Close (); Return Encoding.UTF8.GetString (Ms.
    ToArray ()); ///<summary>///3DES decryption///</summary>///<param name= "Value" with specified keys and vectors ></param&gt
    ; <param name= "SKey" ></param>///<param name= "SIV" ></param>///<returns></ret Urns> public string Decrypt3des (String str, string SKey, String sivs) {SymmetricAlgorithm MCSP = new Trip
      Ledescryptoserviceprovider ();
      ICryptoTransform CT;
      MemoryStream MS;
      CryptoStream CS;
      Byte[] byt;
      Mcsp.key = convert.frombase64string (SKey);
      MCSP.IV = convert.frombase64string (SIV);
      Mcsp.mode = System.Security.Cryptography.CipherMode.ECB;
      mcsp.padding = System.Security.Cryptography.PaddingMode.PKCS7;
      ct = Mcsp.createdecryptor (Mcsp.key, MCSP.IV);
      BYT = convert.frombase64string (str);
      ms = new MemoryStream (); CS = new CryPtostream (MS, CT, cryptostreammode.write); Cs. Write (byt, 0, Byt.
      Length); Cs.
      FlushFinalBlock (); Cs.
      Close (); Return Encoding.UTF8.GetString (Ms.
    ToArray ()); #endregion #region A simple encryption decryption method that only supports English public static string Encryptenstr (String str)//Reverse plus 1 encryption {byte [] by = new BYTE[STR.
      Length];
       for (int i = 0; I <= str.
       Length-1;
      i++) {By[i] = (byte) ((byte) str[i] + 1);
      } str = ""; for (int i = by.
       Length-1;
       I >= 0; i--) {str = ((char) by[i]).
      ToString ();
    return str; public static string Decryptenstr (String str)//order minus 1 decoding {byte[] by = new BYTE[STR.
      Length];
       for (int i = 0; I <= str.
       Length-1;
      i++) {By[i] = (byte) ((byte) str[i]-1);
      } str = ""; for (int i = by.
       Length-1;
       I >= 0; i--) {str = ((char) by[i]).
      ToString ();
return str;    #endregion #region A simple encryption decryption method that supports the Chinese public static string Encryptcnstr (String str) {St on the previous basis Ring Htext = ""; blank text for (int i = 0; i < str.) Length;
      i++) {Htext = Htext + (char) (Str[i] + 10-1 * 2);
    return htext;
      public static string Decryptcnstr (String str) {string dtext = ""; for (int i = 0; i < str. Length;
      i++) {Dtext = Dtext + (char) (Str[i]-10 + 1 * 2);
    return dtext; #endregion #region URL Address codec///<summary>///encoded URL///</summary>///<param
      Name= "url" ></param>///<returns></returns> public static string UrlEncode (string url) {
      byte[] MByte = null; MByte = System.Text.Encoding.GetEncoding ("GB2312").
      GetBytes (URL);
    Return System.Web.HttpUtility.UrlEncode (MByte); ///<summary>///decoding URL address///</summary>///<paramName= "url" ></param>///<returns></returns> public static string UrlDecode (string url) {
    Return Httputility.urldecode (URL, System.Text.Encoding.GetEncoding ("GB2312"));
 } #endregion

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