using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.Mvc;

using System.Text;

using System.Web.Routing;

using System.Security.Cryptography;

using System.IO;

using System;

​

public static class MyExtensions

{

    public static MvcHtmlString EncodedActionLink(this HtmlHelper htmlHelper, string linkText, string actionName, string controllerName, object routeValues, object htmlAttributes)

    {

        string queryString = string.Empty;

        string htmlAttributesString = string.Empty;

        if (routeValues != null)

        {

            RouteValueDictionary d = new RouteValueDictionary(routeValues);

            for (int i = 0; i < d.Keys.Count; i++)

            {

                if (i > 0)

                {

                    queryString += "?";

                }

                queryString += d.Keys.ElementAt(i) + "=" + d.Values.ElementAt(i);

            }

        }

​

        if (htmlAttributes != null)

        {

            RouteValueDictionary d = new RouteValueDictionary(htmlAttributes);

            for (int i = 0; i < d.Keys.Count; i++)

            {

                htmlAttributesString += " " + d.Keys.ElementAt(i) + "=" + d.Values.ElementAt(i);

            }

        }

​

        //What is Entity Framework??

        StringBuilder ancor = new StringBuilder();

        ancor.Append("<a ");

        if (htmlAttributesString != string.Empty)

        {

            ancor.Append(htmlAttributesString);

        }

        ancor.Append(" href='");

        if (controllerName != string.Empty)

        {

            ancor.Append("/" + controllerName);

        }

​

        if (actionName != "Index")

        {

            ancor.Append("/" + actionName);

        }

        if (queryString != string.Empty)

        {

            ancor.Append("?q=" + Encrypt(queryString));

        }

        ancor.Append("'");

        ancor.Append(">");

        ancor.Append(linkText);

        ancor.Append("");

        return new MvcHtmlString(ancor.ToString());

    }

​

    private static string Encrypt(string plainText)

    {

        string key = "jdsg432387#";

        byte[] EncryptKey = { };

        byte[] IV = { 55, 34, 87, 64, 87, 195, 54, 21 };

        EncryptKey = System.Text.Encoding.UTF8.GetBytes(key.Substring(0, 8));

        DESCryptoServiceProvider des = new DESCryptoServiceProvider();

        byte[] inputByte = Encoding.UTF8.GetBytes(plainText);

        MemoryStream mStream = new MemoryStream();

        CryptoStream cStream = new CryptoStream(mStream, des.CreateEncryptor(EncryptKey, IV), CryptoStreamMode.Write);

        cStream.Write(inputByte, 0, inputByte.Length);

        cStream.FlushFinalBlock();

        return Convert.ToBase64String(mStream.ToArray());

    }

}

​

​

​

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]

public class EncryptedActionParameterAttribute : ActionFilterAttribute

{

    public override void OnActionExecuting(ActionExecutingContext filterContext)

    {

​

        Dictionary<string, object> decryptedParameters = new Dictionary<string, object>();

        if (HttpContext.Current.Request.QueryString.Get("q") != null)

        {

            string encryptedQueryString = HttpContext.Current.Request.QueryString.Get("q");

            string decrptedString = Decrypt(encryptedQueryString.ToString());

            string[] paramsArrs = decrptedString.Split('?');

​

            for (int i = 0; i < paramsArrs.Length; i++)

            {

                string[] paramArr = paramsArrs[i].Split('=');

                decryptedParameters.Add(paramArr[0], Convert.ToInt32(paramArr[1]));

            }

        }

        for (int i = 0; i < decryptedParameters.Count; i++)

        {

            filterContext.ActionParameters[decryptedParameters.Keys.ElementAt(i)] = decryptedParameters.Values.ElementAt(i);

        }

        base.OnActionExecuting(filterContext);

​

    }

​

    private string Decrypt(string encryptedText)

    {

        string key = "jdsg432387#";

        byte[] DecryptKey = { };

        byte[] IV = { 55, 34, 87, 64, 87, 195, 54, 21 };

        byte[] inputByte = new byte[encryptedText.Length];

​

        DecryptKey = System.Text.Encoding.UTF8.GetBytes(key.Substring(0, 8));

        DESCryptoServiceProvider des = new DESCryptoServiceProvider();

        inputByte = Convert.FromBase64String(encryptedText);

        MemoryStream ms = new MemoryStream();

        CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(DecryptKey, IV), CryptoStreamMode.Write);

        cs.Write(inputByte, 0, inputByte.Length);

        cs.FlushFinalBlock();

        System.Text.Encoding encoding = System.Text.Encoding.UTF8;

        return encoding.GetString(ms.ToArray());

    }

}

​

​