Image Handling In ASP.NET

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;


public partial class addWaterMark : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void btnAddWaterMark_Click(object sender, EventArgs e)
    {
        if (FileUpload1.HasFile)
        {
            byte[] imgbyte = FileUpload1.FileBytes;
            //creating object of ImageHandler Class
            ImageHandler imageHandler = new ImageHandler();
            System.Drawing.Image imageWithWatermark = imageHandler.AddWatermarkText(imgbyte, txtWaterMarkText.Text);
            if (imageWithWatermark != null)
            {
                //file name to save
                string saveFileName = Guid.NewGuid().ToString() + ".jpg";
                //saving image in current root location
                imageWithWatermark.Save(Server.MapPath(saveFileName));
                //displaying image file in a Image Control
                Image1.ImageUrl = saveFileName;
                imageWithWatermark.Dispose();
            }
            else
            {
                if (imageHandler.havException)
                {
                    Response.Write(imageHandler.ExceptionMessage);
                }
            }
        }
    }
}