Simple C# encryption and decryption
January 20th, 2011 by Rémy Blättler
There are various ways to encrypt and decrypt a string in with .Net. The simplest is to use Base64. But this just makes the string unreadable for a human, but it is not a real encryption. Although, for most case is is likely enough.
If you want something a little fancier, I have a simple solution for you:
public static String Encrypt(string source)
{
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
byte[] Key = { 12, 13, 14, 15, 16, 17, 18, 19 };
byte[] IV = { 12, 13, 14, 15, 16, 17, 18, 19 };
ICryptoTransform encryptor = des.CreateEncryptor(Key, IV);
try
{
byte[] IDToBytes = ASCIIEncoding.ASCII.GetBytes(source);
byte[] encryptedID = encryptor.TransformFinalBlock(IDToBytes, 0, IDToBytes.Length);
return Convert.ToBase64String(encryptedID);
}
catch (FormatException)
{
return null;
}
catch (Exception)
{
throw;
}
}
public static string Decrypt(string encrypted)
{
byte[] Key = { 12, 13, 14, 15, 16, 17, 18, 19 };
byte[] IV = { 12, 13, 14, 15, 16, 17, 18, 19 };
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
ICryptoTransform decryptor = des.CreateDecryptor(Key, IV);
try
{
byte[] encryptedIDToBytes = Convert.FromBase64String(encrypted);
byte[] IDToBytes = decryptor.TransformFinalBlock(encryptedIDToBytes, 0, encryptedIDToBytes.Length);
return ASCIIEncoding.ASCII.GetString(IDToBytes);
}
catch (FormatException)
{
return null;
}
catch (Exception)
{
throw;
}
}
Just make sure that you replace the Key and IV values.
I had to use the Base64 Encoding in addition to the encryption so you can use the result string like a normal string and write it somewhere. Otherwise it could contain non ASCII characters and you couldn’t easily use it.
If you want to use the encrypted string in a url, you should HTML encode it too:
System.Web.HttpUtility.UrlEncode(Encrypt(mystring));
Have fun and let me know if you have any questions.