How to download file from url that redirects?

Question

i\'m trying to download a file from a link that doesn\'t contain the file, but instead it redirects to another (temporary) link that contains the actual file. The objective

Answer 1

I switched from a WebClient based approach to a HttpWebRequest too because auto redirects didn't seem to be working with WebClient. I was using similar code to yours but could never get it to work, it never redirected to the actual file. Looking in Fiddler I could see I wasn't actually getting the final redirect.

Then I came across some code for a custom version of WebClient in this question:

class CustomWebclient: WebClient
{
  [System.Security.SecuritySafeCritical]
  public CustomWebclient(): base()
  {
  }

  public CookieContainer cookieContainer = new CookieContainer();

  protected override WebRequest GetWebRequest(Uri myAddress)
  {
    WebRequest request = base.GetWebRequest(myAddress);
    if (request is HttpWebRequest)
    {
      (request as HttpWebRequest).CookieContainer =   cookieContainer;
      (request as HttpWebRequest).AllowAutoRedirect = true;
    }
    return request;
  }
}

The key part in that code is AllowAutoRedirect = true, it's supposed to be on by default according to the documentation, which states:

AllowAutoRedirect is set to true in WebClient instances.

but that didn't seem to be the case when I was using it.

I also needed the CookieContainer part for this to work with the SharePoint external URLs we were trying to access.