ASP. NET string encryption and decryption

1 usingSystem;2 usingSystem.Data;3 usingSystem.Configuration;4 usingsystem.web;5 usingSystem.Web.Security;6 usingSystem.Web.UI;7 usingSystem.Web.UI.WebControls;8 usingSystem.Web.UI.WebControls.WebParts;9 usingSystem.Web.UI.HtmlControls;Ten usingSystem.Xml; One usingSystem.Data.SqlClient; A usingSystem.IO; - usingSystem.Net; - usingSystem.Text; the usingSystem.Text.RegularExpressions; - usingSystem.Security.Cryptography; -  -  + /// <summary> -     ///Encrypt +     /// </summary> A     /// <param name= "Ptoencrypt" >the string to encrypt</param> at     /// <param name= "SKey" >Encryption Key Example: "ABCDEFGH"</param> -     /// <returns></returns> -      Public stringEncrypt (stringptoencrypt) -     { -         stringSKey ="ABCDEFGH"; -DESCryptoServiceProvider des =NewDESCryptoServiceProvider ();//Put the string in a byte array in         byte[] Inputbytearray =Encoding.Default.GetBytes (ptoencrypt); -         //byte[] Inputbytearray=encoding.unicode.getbytes (ptoencrypt);  toDes. Key = ASCIIEncoding.ASCII.GetBytes (SKey);//establish keys and offsets for encrypted objects +DES.IV = ASCIIEncoding.ASCII.GetBytes (SKey);//GetBytes method of using Asciiencoding.ascii method in original text -MemoryStream ms =NewMemoryStream ();//make the input password must be entered in English text theCryptoStream cs =NewCryptoStream (MS, Des. CreateEncryptor (), cryptostreammode.write); *Cs. Write (Inputbytearray,0, inputbytearray.length); $ cs. FlushFinalBlock ();Panax NotoginsengStringBuilder ret =NewStringBuilder (); -         foreach(byteBinchMs. ToArray ()) the         { +Ret. AppendFormat ("{0:x2}", b); A         } the ret. ToString (); +         returnret. ToString (); -     } $     /// <summary> $     ///decryption -     /// </summary> -     /// <param name= "Ptodecrypt" >to decrypt a string</param> the     /// <param name= "SKey" >Decryption Key Example: "ABCDEFGH"</param> -     /// <returns></returns>Wuyi      Public stringDecrypt (stringptodecrypt) the     { -         stringSKey ="ABCDEFGH"; WuDESCryptoServiceProvider des =NewDESCryptoServiceProvider (); -         byte[] Inputbytearray =New byte[Ptodecrypt.length/2]; About          for(intx =0; X < Ptodecrypt.length/2; X + +) $         { -             inti = (Convert.ToInt32 (ptodecrypt.substring (x *2,2), -)); -INPUTBYTEARRAY[X] = (byte) I; -         } ADes. Key = ASCIIEncoding.ASCII.GetBytes (SKey);//establishes the key and offset of the encrypted object, which is important and cannot be modified +DES.IV =ASCIIEncoding.ASCII.GetBytes (SKey); theMemoryStream ms =NewMemoryStream (); -CryptoStream cs =NewCryptoStream (MS, Des. CreateDecryptor (), cryptostreammode.write); $Cs. Write (Inputbytearray,0, inputbytearray.length); the cs. FlushFinalBlock (); theStringBuilder ret =NewStringBuilder ();//Create Stringbuild object, Createdecrypt use Stream object, must turn decrypted text into stream object the         returnSystem.Text.Encoding.Default.GetString (Ms. ToArray ()); the}