How to upload and download files thru FTP Server?

I have use several references in creating this window application. I have somehow simplified it and extract codes from the references that I have used. There is only three buttons, they are upload, download and close. The upload button is used to copy file to ftp server. In short You are transferring or copying your local file to ftp server. The download button is used to get file from ftp server to your local folder or machine. The close button is used to close your application.

Here is what the application looks like,

Here is my code

Here are my references that I have used in this blog:
Code Project
C# Corner
Code Guru
MSDN Microsoft
ondotnet