Icon Inside a Gridview

 Download Image From inside a gridview

protected void GridView1_RowCommand1(object sender, GridViewCommandEventArgs e)
        {

            if (e.CommandName=="Download")
            {
                
                int i = Convert.ToInt32(e.CommandArgument);
                GridViewRow r = GridView1.Rows[i];
                Image l1 = (Image)r.FindControl("Image1");
               
                string strurl = l1.ImageUrl ;
                WebClient req = new WebClient();

                Response.Clear();
                Response.ContentType = "application/octet-stream";
                Response.AppendHeader("content-disposition", "filename=\""+ Server.MapPath(strurl) + "\"");

                byte[] data = req.DownloadData(Server.MapPath(strurl));
                Response.BinaryWrite(data);
                Response.End();
               
            }
           else if (e.CommandName.Equals("select"))
            {
                mpe.Show();
                int index = Convert.ToInt32(e.CommandArgument);
                GridViewRow row = GridView1.Rows[index];
              
            }

        }

using System;
using System.Buffers.Text;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Windows.Input;

namespace EncryptedandDecrypted
{
    public partial class EncryptedAndDecrypted : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
                byte[] plainTextBytes = Encoding.UTF8.GetBytes(TextEncrypt.Text);
                string TextDecrypt = Convert.ToBase64String(plainTextBytes);
              //  Response.Write( TextDecrypt); 
        } 
        protected void Button1_Click(object sender, EventArgs e)
        {
            try
            {
                string encrypted = Convert.ToString(TextEncrypt.Text);
                TextDecrypt.Text = "";
                string publickey = "santhosh";
                string secretkey = "engineer";
                byte[] secretkeyByte = { };
                secretkeyByte = Encoding.UTF8.GetBytes(secretkey);
                byte[] publickeybyte = { };
                publickeybyte = Encoding.UTF8.GetBytes(publickey);
                MemoryStream ms = null;
                CryptoStream cs = null;
                byte[] encryptedResult = Encoding.UTF8.GetBytes(encrypted);
                RijndaelManaged aes = new RijndaelManaged();
                aes.KeySize = 256;
                aes.BlockSize = 256;
                aes.Padding = PaddingMode.Zeros;
                aes.Mode = CipherMode.CBC;
                byte[] encodedTextBytes = Encoding.UTF8.GetBytes(TextEncrypt.Text);
                TextDecrypt.Text = Convert.ToBase64String(encodedTextBytes);

              //  Response.Write(TextDecrypt.Text);
                //  var toDecodeAsString = System.Convert.FromBase64String(encrypted);
                using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
                {
                    RijndaelManaged AES = new RijndaelManaged();
                    AES.KeySize = 256;
                    AES.BlockSize = 128;
                    ms = new MemoryStream();
                    cs = new CryptoStream(ms, des.CreateEncryptor(publickeybyte, secretkeyByte), CryptoStreamMode.Write);
                    cs.Write(encryptedResult, 0, encryptedResult.Length);
                    cs.FlushFinalBlock();
                    Label1.Text = TextDecrypt.Text;
                    TextDecrypt.Text = "";
                    Label2.Text = "";
                    //TextDecrypt.Text = Convert.ToBase64String(ms.ToArray());      
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message, ex.InnerException);
            }
        }
        protected void Button2_Click(object sender, EventArgs e)
        {
            try
            {
                string Decrypt = Convert.ToString(TextDecrypt.Text);
              //  TextEncrypt.Text = "";
                string publickey = "santhosh";
                string privatekey = "engineer";
                RijndaelManaged aesAlg = null;
                byte[] privatekeyByte = { };
                privatekeyByte = Encoding.UTF8.GetBytes(privatekey);
                byte[] publickeybyte = { };
                publickeybyte = Encoding.UTF8.GetBytes(publickey);
                MemoryStream ms = null;
                CryptoStream cs = null;
                aesAlg = new RijndaelManaged();
                RijndaelManaged aes = new RijndaelManaged();
                aes.KeySize = 256;
                aes.BlockSize = 256;
                aes.Padding = PaddingMode.Zeros;
                aes.Mode = CipherMode.CBC;
                byte[] bytes = Convert.FromBase64String(TextDecrypt.Text);
                TextEncrypt.Text = Convert.ToBase64String(bytes);
                byte[] inputbyteArray = new byte[Decrypt.Replace(" ", "+").Length];
                inputbyteArray = Convert.FromBase64String(Decrypt.Replace(" ", "+"));
                using (DESCryptoServiceProvider DES = new DESCryptoServiceProvider())
                {
                    ms = new MemoryStream(bytes);
                    cs = new CryptoStream(ms, DES.CreateDecryptor(publickeybyte, privatekeyByte), CryptoStreamMode.Write);
                    cs.Write(bytes, 0, bytes.Length);
                    Encoding encoding = Encoding.UTF8;
                    TextEncrypt.Text = encoding.GetString(ms.ToArray());
                    Label2.Text = TextEncrypt.Text;
                    TextEncrypt.Text = "";
                    Label1.Text = ""; 
                }   
            }
            catch (Exception ae)
            {
                throw new Exception(ae.Message, ae.InnerException);
            }
        }
    }
}

    ValidationExpression="[a-zA-Z ]*$" ErrorMessage="*Valid characters: Alphabets and space." ForeColor="#FF3300" />

Thank you all

test this