C# download file from the web with login

Question

I can already login to the web page with redirect (i am saving cookies) with this code

   CookieCollection cookies = new CookieCollection();
        HttpWeb         


        

Answer 1

This should do the job!

        CookieContainer cookieJar = new CookieContainer();
        CookieAwareWebClient http = new CookieAwareWebClient(cookieJar);

        string postData = "name=********&password=*********&submit=submit";
        string response = http.UploadString("https://www.loginpage.com/", postData);

        // validate your login! 

        http.DownloadFile("https://www.loginpage.com/export_excel.php?export_type=list", "my_excel.xls");

I have used CookieAwareWebClient

public class CookieAwareWebClient : WebClient
{
    public CookieContainer CookieContainer { get; set; }
    public Uri Uri { get; set; }

    public CookieAwareWebClient()
        : this(new CookieContainer())
    {
    }

    public CookieAwareWebClient(CookieContainer cookies)
    {
        this.CookieContainer = cookies;
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
        WebRequest request = base.GetWebRequest(address);
        if (request is HttpWebRequest)
        {
            (request as HttpWebRequest).CookieContainer = this.CookieContainer;
        }
        HttpWebRequest httpRequest = (HttpWebRequest)request;
        httpRequest.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
        return httpRequest;
    }

    protected override WebResponse GetWebResponse(WebRequest request)
    {
        WebResponse response = base.GetWebResponse(request);
        String setCookieHeader = response.Headers[HttpResponseHeader.SetCookie];

        if (setCookieHeader != null)
        {
            //do something if needed to parse out the cookie.
            if (setCookieHeader != null)
            {
                Cookie cookie = new Cookie(); //create cookie
                this.CookieContainer.Add(cookie);
            }
        }
        return response;
    }
}

---

Source & Credit for : CookieAwareWebClient

Answer 2

If the client account is already a valid user of the site you just need to use the default credentials before downloading, like so..

WebClient Client=new WebClient();
Client.UseDefaultCredentials=true;
Client.DownloadFile(url, destination);