Question

experts. I’m trying to create a simple file downloader (with GUI). I’m pretty new to Vb.net and I didn’t find any usefull information about this in the books I own. All tutorials in the wild are making me more frustrated, since the snippets I use, in most cases, are different classes.
So I have some basic questions:

• What should I use? HttpWebRequest/HttpWebResponse or
  FileWebRequest/FileWebResponse?
• How do I save the ResponseStream to a file ?
• Is it possible to use ResponseStream to define the kind of File (FileInfo) Class to get basic file information (size, extension, etc)
  • is it generally neccessary, if GetResponse().headers gives you most
    of this info ?

My code, which sucks, because I do not know how to realize the saving….

Private Sub btn_downloader_Click(ByVal sender...) Handles btn_downloader.Click
     'e.g http://codeigniter.com/download.php'
     Dim fileUrl As String = txtBox_url.Text 
     Dim webUri = New Uri(fileUrl)
     Dim wReq As HttpWebRequest = WebRequest.Create(webUri)
     Dim wRes As HttpWebResponse = wReq.GetResponse()
     Dim resUri As Uri = wRes.ResponseUri
     'to ckeck if http://codeigniter.com/download.php gives http://codeigniter.com/download_files/reactor/CodeIgniter_2.0.0.zip and it does!'
     Dim resStream As Stream = wRes.GetResponseStream()

And now I have to somehow use one of the Stream methods to write the file (at this stage only as a Stream), but do not know how.
I saw this in the tutorials

resStream.Read(buffer, offset, count)

but I don’t know what the buffer is and what it is for. Should I set some static values or any dynamic which deppends on Stream-data ?

Need help!

P.S. Sorry for bad English

Answer 1

If you are looking to do it quickly without a progress bar or anything that tracks download speed, estimated time left, etc. then I would suggest WebClient.DownloadFileAsync or WebClient.DownloadFile. You should be able to read the mime type with WebClient.ResponseHeaders["content-type"] and then rename the file accordingly.