ÿþusing System;

using System.Globalization;

using System.IO;

using System.Web;



namespace VHelms.Web.Filemanager

{

    public class HttpDownload : IHttpHandler

    {

        public void ProcessRequest(HttpContext context)

        {

            try

            {

                if (!string.IsNullOrEmpty(context.Request["File"]))

                {

                    string fileName = context.Request["File"];

                    DownloadFile(fileName, context);

                }

                else

                {

                    throw new ArgumentException("The File-ID is not available anymore. Please reload the page and try again.");

                }

            }

            catch (Exception ex)

            {

                context.Response.ContentType = "text/plain";

                context.Response.Write(string.Format("Error:\r\n{0}", ex));

            }

        }



        public bool IsReusable

        {

            get { return true; }

        }



        /// <summary>

        /// 

        /// </summary>

        /// <param name="filepath"></param>

        /// <param name="context"></param>

        private static void DownloadFile(string filepath, HttpContext context)

        {

            HttpResponse response = context.Response;

            // Buffer to read 10K bytes in chunk:

            var buffer = new Byte[10000];

            // Identify the file name.

            string filename = Path.GetFileName(filepath);

            string appPath = context.Request.PhysicalApplicationPath;

            string completeFilePath = appPath + filename;

            FileStream fileStream = null;

            try

            {

                // Open the file.

                fileStream = new FileStream(completeFilePath, FileMode.Open, FileAccess.Read, FileShare.Read);



                // Total bytes to read:

                long dataToRead = fileStream.Length;

                response.ContentType = "application/octet-stream";

                response.AddHeader("Content-Disposition", "attachment; filename=" + filename);

                response.AddHeader("Content-Length", fileStream.Length.ToString());



                // Read the bytes.

                while (dataToRead > 0)

                {

                    // Verify that the client is connected.

                    if (response.IsClientConnected)

                    {

                        // Read the data in buffer.

                        int length = fileStream.Read(buffer, 0, 10000);



                        // Write the data to the current output stream.

                        response.OutputStream.Write(buffer, 0, length);



                        // Flush the data to the HTML output.

                        response.Flush();



                        buffer = new Byte[10000];

                        dataToRead = dataToRead - length;

                    }

                    else

                    {

                        //prevent infinite loop if user disconnects

                        dataToRead = -1;

                    }

                }

            }

            catch (Exception ex)

            {

                // Trap the error, if any.

                response.ContentType = "text/plain";

                response.Write(string.Format("Error:\r\n{0}", ex));

                //Response.Write("Error : " + ex.Message);

            }

            finally

            {

                if (fileStream != null)

                {

                    //Close the file.

                    fileStream.Close();

                }



                // delete tmp file, if the file is stored in the temp directory

                if (filepath.StartsWith(Path.GetTempPath()))

                {

                    // delete temp file

                    var tempFile = new FileInfo(filepath);

                    tempFile.Delete();

                }

            }

        }

    }

}