Download file over HTTPS using .NET (dotnet)

Question

I would like to download a file using VB.NET (preferably) or C# via HTTPS.

I have this code to download a file over plain HTTP:

Dim client As WebClie         


        

Answer 1

You just need to point that address to your HTTPS resource and to inform your credential:

client.Credentials = new NetworkCredential("username", "password");
client.DownloadFile("https://your.resource.here", @"localfile.jog")

You're talking about how to log into a site protected by a HTML form login. I wrote this code sometime ago and you could to adapt it to login into your remote site: Orkut Login Code

Things you need to keep in mind:

• If that's an ASP.NET site, you need to call it first to get __EVENTTARGET and __EVENTARGUMENT values, as they're required to process your login postback. If it's not, skip this step.
• You need to identify that names that site uses to fill your username and password
• You must to add a CookieContainer. It keeps your login cookie, so subsequent calls uses that authenticated context.
• After all that, you should be able to get your remote resource and to download it

Answer 2

You need to add a certificate validator:

// You need to call it only once in a static constructor or multiple times there is no problem
ServicePointManager.ServerCertificateValidationCallback = ValidateCertificate;

    private static bool ValidateCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
    {
        return true;
    }

In VB:

ServicePointManager.ServerCertificateValidationCallback = AddressOf ValidateCertificate
Dim client As WebClient = New WebClient()
'...
'Your code

  Private Shared Function ValidateCertificate(sender As Object, certificate As X509Certificate, chain As X509Chain, sslPolicyErrors As SslPolicyErrors) As Boolean
        return True
  End Function

Answer 3

Try something like this

        WebClient wc = new WebClient();
        wc.UseDefaultCredentials = false;

        CredentialCache creds = new CredentialCache();
        creds.Add(new Uri(url), "Basic",new NetworkCredential(username, password, domain));

        wc.Credentials = creds;
        wc.Headers.Add(HttpRequestHeader.UserAgent,"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;");
        //wc.Headers["Accept"] = "/";

        wc.DownloadFile(url,localpath);