C # Common string encryption and decryption method encapsulation code

  This article mainly introduces C # common string encryption and decryption method package code, the need for friends can refer to the

    Code as follows://Method I//must add to the system.web reference//using System.Web.Security; <summary>///SHA1 Encrypted string///</summary>///<param name= "source" > Source string </param>///<returns > Encrypted string </returns> public string SHA1 (string source) {    return FormsAuthentication.HashPasswordForStoringInConfigFile (source, "SHA1"); ///<summary>///MD5 Cryptographic string///</summary>///<param name= "source" > Source string </param>///<returns > Encrypted string </returns> public string MD5 (string source) {    return FormsAuthentication.HashPasswordForStoringInConfigFile (source, "MD5");; }    /Method II (Reversible encryption decryption)://using System.Security.Cryptography; public string Encode (string data) {    byte[] Bykey = System.Text.ASCIIEncoding.ASCII.GetBytes (key_64);     byte[] Byiv = System.Text.ASCIIEncoding.ASCII.GetBytes (iv_64);     DESCryptoServiceProvider CryptoProvider = new DESCryptoServiceProvider ();     INT i =Cryptoprovider.keysize;     MemoryStream ms = new MemoryStream ();     CryptoStream CST = new CryptoStream (MS, Cryptoprovider.createencryptor (Bykey, Byiv), CryptoStreamMode.Write);     StreamWriter sw = new StreamWriter (CST);     SW. Write (data);     SW. Flush ();     CST. FlushFinalBlock ();     SW. Flush ();     Return convert.tobase64string (Ms. GetBuffer (), 0, (int) Ms. Length); public string Decode (string data) {    byte[] Bykey = System.Text.ASCIIEncoding.ASCII.GetBytes (key_64); &nbsp ;   byte[] Byiv = System.Text.ASCIIEncoding.ASCII.GetBytes (iv_64);     byte[] Byenc;     Try     {        BYENC = convert.frombase64string (data);    } &nbs P   Catch     {        return null;    }     Descryptoserviceprovid Er cryptoprovider = new DESCryptoServiceProvider ();     MemorystreaM ms = new MemoryStream (BYENC);     CryptoStream CST = new CryptoStream (MS, Cryptoprovider.createdecryptor (Bykey, Byiv), CryptoStreamMode.Read);     StreamReader sr = new StreamReader (CST);    /Method III (MD5 irreversible)://using System.Security.Cryptography; MD5 irreversible encryption//32-bit encryption public string getmd5_32 (string s, String _input_charset) {    MD5 MD5 = new Md5cryptoservice Provider ();     byte[] t = Md5.computehash (encoding.getencoding (_input_charset). GetBytes (s));     StringBuilder sb = new StringBuilder (32);     for (int i = 0; i < t.length i++)     {        SB. Append (T[i]. ToString ("X"). PadLeft (2, ' 0 '));    }     return SB. ToString (); }//16-bit encryption public static string Getmd5_16 (String convertstring) {    MD5CryptoServiceProvider MD5 = new Md5crypt Oserviceprovider ();     String t2 = bitconverter.tostring (Md5.computehash UTF8Encoding.Default.GetBytes (convertstring)), 4, 8);     t2 = t2. Replace ("-", "");     return T2; }    /method four (symmetric encryption)://using System.IO; Using System.Security.Cryptography; Private SymmetricAlgorithm Mobjcryptoservice; private string Key; <summary>   ///Symmetric cryptographic class constructors   ///</summary>    public Symmetricmethod () {     Mobjcryptoservice = new RijndaelManaged ();     Key = "Guz (%&hj7x89h$yubi0456ftmat5&fvhufcy76*h% hilj$lhj!y6& (*jkp87jh7;}///<summary >   ///access key   ///</summary>   ///<returns> key </returns>  & nbsp Private byte[] Getlegalkey () {    string stemp = Key;     Mobjcryptoservice.generatekey ();   &NB Sp byte[] Byttemp = Mobjcryptoservice.key;     int keylength = byttemp.length;     if (Stemp.length > Keylength)         stemp = stemp.substring (0, keylength);     ELSE if(Stemp.length < Keylength)         stemp = Stemp.padright (Keylength, "");     return ASCIIEncoding.ASCII.GetBytes (stemp); ///<summary>   ///get initial vector iv   ///</summary>   ///<returns> First-class vector iv& Lt;/returns>    Private byte[] Getlegaliv () {    string stemp = "E4ghj*ghg7!rnifb&95guy86gfgh UB#ER57HBH (U%G6HJ ($jhWk 7&!hg4ui% $HJK ";     MOBJCRYPTOSERVICE.GENERATEIV ();     byte[] Byttemp = MOBJCRYPTOSERVICE.IV;     int ivlength = byttemp.length;     if (Stemp.length > Ivlength)         stemp = stemp.substring (0, ivlength);     ELSE if (Stemp.length < ivlength)         stemp = Stemp.padright (Ivlength, "");     return ASCIIEncoding.ASCII.GetBytes (stemp); ///<summary>   ///encryption method   ///</summary>   ///<param name= "Source" > strings to be encrypted</param>   ///<returns> Encrypted string </returns>    public string Encrypto (string SOURCE) {    byte[] Bytin = UTF8Encoding.UTF8.GetBytes (source);     MemoryStream ms = new Memorystrea M ();     Mobjcryptoservice.key = Getlegalkey ();     MOBJCRYPTOSERVICE.IV = Getlegaliv ();     ICryptoTransform encrypto = Mobjcryptoservice.createencryptor ();     CryptoStream cs = new CryptoStream (MS, Encrypto, CryptoStreamMode.Write);     CS. Write (bytin, 0, bytin.length);     CS. FlushFinalBlock ();     Ms. Close ();     byte[] Bytout = Ms. ToArray ();     return convert.tobase64string (bytout); ///<summary>   ///decryption method   ///</summary>   ///<param name= "Source" > strings to decrypt </param>   ///<returns> decrypted string </returns>    public string Decrypto (string Source) {    byte[] Bytin = ConVert. FromBase64String (Source);     MemoryStream ms = new MemoryStream (bytin, 0, bytin.length);     Mobjcryptoservice.key = Getlegalkey ();     MOBJCRYPTOSERVICE.IV = Getlegaliv ();     ICryptoTransform encrypto = Mobjcryptoservice.createdecryptor ();     CryptoStream cs = new CryptoStream (MS, Encrypto, CryptoStreamMode.Read);     StreamReader sr = new StreamReader (CS);     return Sr. ReadToEnd ();  //Method V://using System.IO; Using System.Security.Cryptography; Using System.Text; Default key vector private static byte[] keys = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}; /**//**//**////<summary>///des encrypted string keleyi.com///</summary>///<param name= "EncryptString" > The strings to be encrypted </param>///<param name= "Encryptkey" > Encryption keys, which require a successful return of the encrypted string for 8-bit </param>///<returns> encryption. Failed to return source string </returns> public static string Encryptdes (String encryptstring, String encryptkey) {    try &nbsP   {        byte[] Rgbkey = Encoding.UTF8.GetBytes (encryptkey.substring (0, 8));     &NB Sp   byte[] Rgbiv = Keys;         byte[] Inputbytearray = Encoding.UTF8.GetBytes (encryptstring);         DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider ();         MemoryStream mstream = new MemoryStream ();         CryptoStream cstream = new CryptoStream (Mstream, Dcsp.createencryptor (Rgbkey, Rgbiv), Cryptos Treammode.write);         Cstream.write (inputbytearray, 0, inputbytearray.length);         Cstream.flushfinalblock ();         return convert.tobase64string (Mstream.toarray ());    }     catch     {        return encryptstring    }}/* *//**//**////<summary>///des decryption string keleyi.com///</summary>///<param name= "decryptstring" > The string to be decrypted </param>///<param name= "Decryptkey" > Decryption key, required 8-bit, same as encryption key </param>///<returns> Decryption successfully returned decrypted string, failed back source string </returns> public static string Decryptdes (String decryptstring, String decryptkey) {  & nbsp Try     {        byte[] Rgbkey = Encoding.UTF8.GetBytes (Decryptkey);       & nbsp byte[] Rgbiv = Keys;         byte[] Inputbytearray = convert.frombase64string (decryptstring);         DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider ();         MemoryStream mstream = new MemoryStream ();         CryptoStream cstream = new CryptoStream (Mstream, DCSP. CreateDecryptor (Rgbkey, Rgbiv), cryptostreammode.write);         Cstream.write (inputbytearray, 0, inputbytearray.length);         Cstream.flushfinalblock ();         return Encoding.UTF8.GetString (Mstream.toarray ());   }     catch     {        return decryptstring    }&NB Sp    /Method VI (File encryption)://using System.IO; Using System.Security.Cryptography; Using System.Text; Encrypted files private static void EncryptData (String inname, String outname, byte[] Deskey, byte[] desiv) {   //creat E The file streams to handle the input and output files.     FileStream fin = new FileStream (inname, FileMode.Open, FileAccess.Read);     FileStream fout = new FileStream (outname, FileMode.OpenOrCreate, FileAccess.Write);     Fout. SetLength (0);    //create variables to help with read and write.     byte[] bin = new byte[100]; This is intermediate storage for the encryption.     Long Rdlen = 0;              //this is the total number of bytes written.     Long Totlen = fin. Length;    //this is the total length of the input FIle.     int Len;                  //this is the number of bytes to written in a Tim E.     des des = new descryptoserviceprovider ();     CryptoStream encstream = new CryptoStream (Fout, Des. CreateEncryptor (Deskey, Desiv), cryptostreammode.write);    //read from the input file, then encrypt and write to the output file.     while (Rdlen < Totlen)     {        len = fin. Read (Bin, 0, 100);         Encstream.write (bin, 0, Len);         Rdlen = Rdlen + len;    }     Encstream.close ();     Fout. Close ();     Fin. Close (); }//Decrypt files private static void Decryptdata (String inname, String outname, byte[] Deskey, byte[] desiv) {   //cre Ate the file streams to handle the input and output files.     FileStream fin = new FileStream (inname, FileMode.Open, fileaccesS.read);     FileStream fout = new FileStream (outname, FileMode.OpenOrCreate, FileAccess.Write);     Fout. SetLength (0);    //create variables to help with read and write.     byte[] bin = new byte[100]; This is intermediate storage for the encryption.     Long Rdlen = 0;              //this is the total number of bytes written.     Long Totlen = fin. Length;    //this is the total length of the input file.     int Len;                  //this is the number of bytes to written in a Tim E.     des des = new descryptoserviceprovider ();     CryptoStream encstream = new CryptoStream (Fout, Des. CreateDecryptor (Deskey, Desiv), cryptostreammode.write);    //read from the input file, then encrypt and write to the output file.     while (Rdlen < Totlen)     {    &nbsp   len = fin. Read (Bin, 0, 100);         Encstream.write (bin, 0, Len);         Rdlen = Rdlen + len;    }     Encstream.close ();     Fout. Close ();     Fin. Close ();     return Sr. ReadToEnd (); }     Detailed source reference: http://www.jb51.net/article/44133.htm