C# file downloader AKA Response.BinaryWrite

For my new project i needed to protect actual location of files on my server and send them to visitor via download page/handler. Below code is a collection of sources found on the internet.

It is a class with 3 different methods. All does same job with a different approach.

using System;
using System.IO;
using System.Web;

public class Download
{


public static void SmallFile(string filename, string filepath, string contentType)
{
try
{
FileStream MyFileStream = new FileStream(filepath, FileMode.Open, FileAccess.Read, FileShare.Read);
long FileSize;
FileSize = MyFileStream.Length;
byte[] Buffer = new byte[(int)FileSize];
MyFileStream.Read(Buffer, 0, (int)MyFileStream.Length);
MyFileStream.Close();
HttpContext.Current.Response.ContentType = contentType;
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8));
HttpContext.Current.Response.BinaryWrite(Buffer);

}
catch
{
HttpContext.Current.Response.ContentType = "text/html";
HttpContext.Current.Response.Write("Downloading Error!");
}
HttpContext.Current.Response.End();
}
public static void LargeFile(string filename, string filepath, string contentType)
{
Stream iStream = null;
// Buffer to read 10K bytes in chunk
//byte[] buffer = new Byte[10000];
// Buffer to read 1024K bytes in chunk


byte[] buffer = new Byte[1048576];

// Length of the file:


int length;
// Total bytes to read:


long dataToRead;

try
{
// Open the file.


iStream = new FileStream(filepath, FileMode.Open, FileAccess.Read, FileShare.Read);
// Total bytes to read:


dataToRead = iStream.Length;
HttpContext.Current.Response.ContentType = contentType;
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8));
// Read the bytes.


while (dataToRead > 0)
{
// Verify that the client is connected.


if (HttpContext.Current.Response.IsClientConnected)
{
// Read the data in buffer.


length = iStream.Read(buffer, 0, 10000);

// Write the data to the current output stream.


HttpContext.Current.Response.OutputStream.Write(buffer, 0, length);

// Flush the data to the HTML output.


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


HttpContext.Current.Response.ContentType = "text/html";
HttpContext.Current.Response.Write("Error : file not found");

}
finally
{
if (iStream != null)
{
//Close the file.


iStream.Close();
}
HttpContext.Current.Response.End();
HttpContext.Current.Response.Close();

}

}
public static void ResumableFile(string filename, string fullpath, string contentType)
{
try
{
FileStream myFile = new FileStream(fullpath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
BinaryReader br = new BinaryReader(myFile);
try
{
HttpContext.Current.Response.AddHeader("Accept-Ranges", "bytes");
HttpContext.Current.Response.Buffer = false;
long fileLength = myFile.Length;
long startBytes = 0;

//int pack = 10240; //10K bytes


int pack = 1048576; //1024K bytes


if (HttpContext.Current.Request.Headers["Range"] != null)
{
HttpContext.Current.Response.StatusCode = 206;
string[] range = HttpContext.Current.Request.Headers["Range"].Split(new char[] { '=', '-' });
startBytes = Convert.ToInt64(range[1]);
}
HttpContext.Current.Response.AddHeader("Content-Length", (fileLength - startBytes).ToString());
if (startBytes != 0)
{
HttpContext.Current.Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength - 1, fileLength));
}
HttpContext.Current.Response.AddHeader("Connection", "Keep-Alive");
HttpContext.Current.Response.ContentType = contentType;
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8));

br.BaseStream.Seek(startBytes, SeekOrigin.Begin);
int maxCount = (int)Math.Floor((double)((fileLength - startBytes) / pack)) + 1;

for (int i = 0; i < maxCount; i++)
{
if (HttpContext.Current.Response.IsClientConnected)
{
HttpContext.Current.Response.BinaryWrite(br.ReadBytes(pack));
}
else
{
i = maxCount;
}
}
}
catch
{
HttpContext.Current.Response.ContentType = "text/html";
HttpContext.Current.Response.Write("Error : file not found");
}
finally
{
br.Close();
myFile.Close();
}
}
catch
{
HttpContext.Current.Response.ContentType = "text/html";
HttpContext.Current.Response.Write("Error : file not found");
}
}

}