How to convert base64String to image?

protected void Button_Click(object sender, EventArgs e)
        {
            byte[] byte_array;
            string base_64_string;
// Remove any blank spaces with + symbol, because it will show error as " Invalid character in a Base-64 string. "
            base_64_string = TextBox.Text.Replace(" ", "+");
// Lenth of the Base-64 string should be multiples of 4, so add one or two equals at the end.
            int count = (base_64_string).Length % 4;
            if (count > 0)
            {
                base_64_string += new string('=', (4 - count));
            }
// Convert from base 64 string to byte[]
            byte_array = Convert.FromBase64String(s);
            ImageHandler.byt = byte_array;
// Call handler class that will convert the byte[] to image URL
            Image.ImageUrl = "ImageHandler.ashx";
        }

using System.Web;
using System.Web.Services;

namespace WebApp
{
    /// 

    /// Summary description for $codebehindclassname$
    /// 

    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class ImageHandler : IHttpHandler
    {
        public static byte[] byt;
        // Converts byte to image and assigns to image control
        public void ProcessRequest(HttpContext context)
        {
            if (byt != null)
            {
                context.Response.ContentType = "image/png/jpeg";
                context.Response.OutputStream.Write(byt, 0, byt.Length);
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}