Encryption/Decryption for the Beginner's Level

Introduction

It often comes to the task list for the College/University level students that they have to store passwords, pass the Query String with URL or other stuff in the Encrypted way. So this trick would focus on the same to provide an easy to understand way of performing this task with minimal time and effort.

Using the Code

I have been doing some coding tasks, when this thing comes into my play, and after searching on GOOGLE, I found the following methods for both Encryption and Decryption.

Hence, I am sharing here for others to get the tasks done in an understandable way.

First of All, I would be telling about the namespaces that are to be included for this.

NameSpaces

using System.Security.Cryptography.X509Certificates;
using System.Net.Security;
using System.IO;
using System.Security.Cryptography; 

Encryption

private string Encrypt(string clearText)
   {
       string EncryptionKey = "KEY"; // See NOTE at end of TIP
       byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
       using (Aes encryptor = Aes.Create())
       {
           Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[]
           { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
           encryptor.Key = pdb.GetBytes(32);
           encryptor.IV = pdb.GetBytes(16);
           using (MemoryStream ms = new MemoryStream())
           {
               using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
               {
                   cs.Write(clearBytes, 0, clearBytes.Length);
                   cs.Close();
               }
               clearText = Convert.ToBase64String(ms.ToArray());
           }
       }
       return clearText;
   }

Decryption

private string Decrypt(string cipherText)
    {
        string EncryptionKey = "KEY"; //See Note at the End of TIP
        cipherText = cipherText.Replace(" ", "+");
        byte[] cipherBytes = Convert.FromBase64String(cipherText);
        using (Aes encryptor = Aes.Create())
        {
            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] 
            { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(cipherBytes, 0, cipherBytes.Length);
                    cs.Close();
                }
                cipherText = Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    } 

NOTE: In place of KEY, you have to provide the key, based on which both Encryption and Decryption will be done. So, the same key would be provided in both methods.

Points of Interest

While I was performing this tip myself, it taught me about the way encryption and decryption works and how they can be implemented in web application.

Comments, positive criticism and advice are heartily welcome. :)