Please see my easy to use command line parsing library:
Enumeration-based Command Line Utility[
^].
I recommend another one published on CodeProject in my article referenced above. If you don't want to use my or any other library, you can simply read how everything works. My article explains it in detail.
How to download files? It depends on protocol. For HTTP, you can use the class
System.Net.HttpWebRequest, for FTP —
System.Net.FtpWebRequest. There is also a simplified class
System.Net.WebClient. Please see:
https://msdn.microsoft.com/en-us/library/system.net.httpwebrequest%28v=vs.110%29.aspx[
^],
https://msdn.microsoft.com/en-us/library/system.net.ftpwebrequest%28v=vs.110%29.aspx[
^],
https://msdn.microsoft.com/en-us/library/system.net.webclient%28v=vs.110%29.aspx[
^].
For a complete example, you can see the full source code of my complete HttpDownloader application, which is, among other things, is capable of completion of downloading of partially downloaded files, if download process was interrupted at any place. Please see:
how to download a file from internet[
^].
See also my past answers:
how to download a file from the server in Asp.net 2.0[
^],
FTP: Download Files[
^].
—SA
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