Download the file from the server side using asp.net

Introduction

In this article we are going to learn the topic of how to download the files from the asp.net application.

In Real time example of user need to download the images . rar files ,log text files etc.,

Coding

Write the below method for downloading the files

private bool DownloadingFiles()

{

//File Path and File Name

string filePath = Server.MapPath("~/");

string _DownloadableProductFileName = "crackers.jpg";

System.IO.FileInfo FileName = new System.IO.FileInfo(filePath + "\\" + _DownloadableProductFileName);

FileStream myFile = new FileStream(filePath + "\\" + _DownloadableProductFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);

//Reads file as binary values

BinaryReader _BinaryReader = new BinaryReader(myFile);

//Check whether file exists in specified location

if (FileName.Exists)

{

try

{

long startBytes = 0;

string lastUpdateTiemStamp = File.GetLastWriteTimeUtc(filePath).ToString("r");

string _EncodedData = HttpUtility.UrlEncode(_DownloadableProductFileName, Encoding.UTF8) + lastUpdateTiemStamp;

Response.Clear();

Response.Buffer = false;

Response.AddHeader("Accept-Ranges", "bytes");

Response.AppendHeader("ETag", "\"" + _EncodedData + "\"");

Response.AppendHeader("Last-Modified", lastUpdateTiemStamp);

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

Response.AddHeader("Content-Disposition", "attachment;filename=" + FileName.Name);

Response.AddHeader("Content-Length", (FileName.Length - startBytes).ToString());

Response.AddHeader("Connection", "Keep-Alive");

Response.ContentEncoding = Encoding.UTF8;

//Send data

_BinaryReader.BaseStream.Seek(startBytes, SeekOrigin.Begin);

//Dividing the data in 1024 bytes package

int maxCount = (int)Math.Ceiling((FileName.Length - startBytes + 0.0) / 1024);

//Download in block of 1024 bytes

int i;

for (i = 0; i < maxCount && Response.IsClientConnected; i++)

{

Response.BinaryWrite(_BinaryReader.ReadBytes(1024));

Response.Flush();

}

//if blocks transfered not equals total number of blocks

if (i < maxCount)

return false;

return true;

}

catch

{

return false;

}

finally

{

Response.End();

_BinaryReader.Close();

myFile.Close();

}

}

else System.Web.UI.ScriptManager.RegisterStartupScript(this, GetType(),

"FileNotFoundWarning", "alert('File is not available now!')", true);

return false;

}

Call this method in one button click method and proceed for downloading