add remove uplaod file throw code on ftp

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

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

    protected void btn_WriteAllFileNameLocal_OnClick(object sender, EventArgs e)
    {
        string localPath = Server.MapPath("\\NewRand");
        string[] files = Directory.GetFiles(localPath);
        foreach (string filepath in files)
        {
            string fileName = Path.GetFileName(filepath);
                   Response.Write(fileName + "<br/>");
        }
    }

    protected void btn_deletefile_OnClick(object sender, EventArgs e)
    {
        string fileName = "a.jpg";

        FtpWebRequest requestFileDelete = (FtpWebRequest)WebRequest.Create("ftp://999999999999/httpdocs/" + fileName);
        requestFileDelete.Credentials = new NetworkCredential("idfcmfindigo", "I@fc34mfindo");
        requestFileDelete.Method = WebRequestMethods.Ftp.DeleteFile;

        FtpWebResponse responseFileDelete = (FtpWebResponse)requestFileDelete.GetResponse();
     
    }

    protected void btn_WriteAllFileName_OnClick(object sender, EventArgs e)
    {
        //done
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://9999999/httpdocs/");
        request.Credentials = new NetworkCredential("idfcmfindigo", "I@fc34mfindo");
        request.Method = WebRequestMethods.Ftp.ListDirectory;
        StreamReader streamReader = new StreamReader(request.GetResponse().GetResponseStream());
        string fileName = streamReader.ReadLine();
        while (fileName != null)
        {
            Response.Write(fileName+"<br/>");
            fileName = streamReader.ReadLine();
        }
        request = null;
        streamReader = null;
    }

    protected void btn_export_OnClick(object sender, EventArgs e)
    {
      

        bool res = this.UploadFile( "c.jpg");
        if (res)
        {
            Response.Write("successfully upload");
        }
        else
        {
            Response.Write("error in upload");
        }
    }

    private bool UploadFile( string fileName)
    {
        string localPath = @"D:\Pramod Raising\RND\NewRand\FTP\";
        //string fileName = "arahimkhan.txt";

        FtpWebRequest requestFTPUploader = (FtpWebRequest)WebRequest.Create("ftp://99999/httpdocs/" + fileName);
        requestFTPUploader.Credentials = new NetworkCredential("idfcmfindigo", "I@fc34mfindo");
        requestFTPUploader.Method = WebRequestMethods.Ftp.UploadFile;

        FileInfo fileInfo = new FileInfo(localPath + fileName);
        FileStream fileStream = fileInfo.OpenRead();

        int bufferLength = 2048;
        byte[] buffer = new byte[bufferLength];

        Stream uploadStream = requestFTPUploader.GetRequestStream();
        int contentLength = fileStream.Read(buffer, 0, bufferLength);

        while (contentLength != 0)
        {
            uploadStream.Write(buffer, 0, contentLength);
            contentLength = fileStream.Read(buffer, 0, bufferLength);
        }

        uploadStream.Close();
        fileStream.Close();

        requestFTPUploader = null;
        return true;
    }

    protected void btn_downloadfile_onclick(object sender, EventArgs e)
    {
        string localPath = @"D:\Pramod Raising\RND\NewRand\FTP\";
        string fileName = "c.jpg";

        FtpWebRequest requestFileDownload = (FtpWebRequest)WebRequest.Create("ftp://99999999/httpdocs/" + fileName);
        requestFileDownload.Credentials = new NetworkCredential("idfcmfindigo", "I@fc34mfindo");
        requestFileDownload.Method = WebRequestMethods.Ftp.DownloadFile;

        FtpWebResponse responseFileDownload = (FtpWebResponse)requestFileDownload.GetResponse();

        Stream responseStream = responseFileDownload.GetResponseStream();
        FileStream writeStream = new FileStream(localPath + fileName, FileMode.Create);

        int Length = 2048;
        Byte[] buffer = new Byte[Length];
        int bytesRead = responseStream.Read(buffer, 0, Length);

        while (bytesRead > 0)
        {
            writeStream.Write(buffer, 0, bytesRead);
            bytesRead = responseStream.Read(buffer, 0, Length);
        }

        responseStream.Close();
        writeStream.Close();

        requestFileDownload = null;
        responseFileDownload = null;
    }

}