mshandler.ashx.txt

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<%@ WebHandler Language="C#" Class="MsHandler" %>
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Web;
using System.Web.Caching;

public class MsHandler : IHttpHandler 
{

    public void ProcessRequest (HttpContext context) 
    {
        // Get the image ID from querystring, and use it to generate a cache key.
        String imageID = context.Request.QueryString["PhotoID"];
        String cacheKey = context.Request.CurrentExecutionFilePath + ":" + imageID;
        Byte[] imageBytes;

        // Check if the cache contains the image.
        Object cachedImageBytes = context.Cache.Get(cacheKey);
        if (cachedImageBytes != null)
        {
            imageBytes = (Byte[])cachedImageBytes;
        }

        else

        {
            // Get image from business layer, and save it into a Byte array as JPEG.
            Image im = PhotoLibrary.GetImage("PhotoID");
            MemoryStream stream = new MemoryStream();
            im.Save(stream, ImageFormat.Jpeg);
            stream.Close();
            im.Dispose();
            imageBytes = stream.GetBuffer();
            
            // Store it in the cache (to be expired after 2 hours).
            context.Cache.Add(cacheKey, imageBytes, null,
            DateTime.MaxValue, new TimeSpan(2, 0, 0),
            CacheItemPriority.Normal, null);
        }

        // Send back image.
        context.Response.ContentType = "image/jpeg";
        context.Response.Cache.SetCacheability(HttpCacheability.Public);
        context.Response.BufferOutput = false;
        context.Response.OutputStream.Write(imageBytes, 0, imageBytes.Length);

    }
    
    public bool IsReusable 
    {

        get 
        {
            return false;
        }
    }

}