encryptDecrypt.cs

using System;
using System.Web;
using System.Security.Cryptography;

public class TestEncrypt
{
	
	const String tokenKey = "x8FWQUedjyiUGlTf5appPQ==";
	const String appCode = "DEMOAPP";
	const String companyCode = "10";
	const String version = "2";
	const String method = "getStudents";
	const String endPoint = "http://api.tasscloud.com.au/tassweb/api/";
	
	public static void Main()
	{
		string original = "{\"currentstatus\":\"current\"}";
		
		var UTF8 = new System.Text.UTF8Encoding();
		var encString = Encrypt( original );
		
		Console.WriteLine("Original:   {0}", original );
		Console.WriteLine("Encrypted:  {0}", encString );
		Console.WriteLine("Decrypted:  {0}", Decrypt( encString ) );
		Console.WriteLine("URL:  {0}?method={1}&appcode={2}&company={3}&v={4}&token={5}", endPoint , method , appCode , companyCode , version , HttpUtility.UrlEncode ( encString ) );
		
	}

	public static string Encrypt (string toEncrypt)
	{
		var UTF8 = new System.Text.UTF8Encoding();
		
		// The Token Key is already Base64.
		byte[] keyArray   	  = Convert.FromBase64String(tokenKey);
		
		// The Paramater String is UTF8.
		byte[] toEncryptArray = UTF8.GetBytes(toEncrypt);

		RijndaelManaged rDel  = new RijndaelManaged();
		rDel.Key              = keyArray;
		rDel.Mode             = CipherMode.ECB;
		rDel.BlockSize        = 128;
		rDel.Padding   		  = PaddingMode.PKCS7;

		ICryptoTransform cTransform  = rDel.CreateEncryptor( keyArray , null );

		byte[] resultArray    = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
		
		return Convert.ToBase64String(resultArray, 0, resultArray.Length);
	}

	public static string Decrypt (string toDecrypt)
	{
		var UTF8 = new System.Text.UTF8Encoding();
		
		// The Token Key is already Base64.
		byte[] keyArray  	  = Convert.FromBase64String(tokenKey);
		
		// The encrypted string is already Base64.
		byte[] toEncryptArray = Convert.FromBase64String(toDecrypt);

		RijndaelManaged rDel  = new RijndaelManaged();
		rDel.Key              = keyArray;
		rDel.Mode             = CipherMode.ECB;
		rDel.BlockSize        = 128;
		rDel.Padding    	  = PaddingMode.PKCS7;
	
		ICryptoTransform cTransform = rDel.CreateDecryptor( keyArray , null );

		byte[] resultArray    = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

		return UTF8.GetString(resultArray);
	}	
}