DownloadFileCompleted

public class Internet
{
private WebClient Client = new WebClient();
public void fileDownloadThread(string url,string saveTo)
{
  Uri u = new Uri(@url);
  Client.DownloadFileCompleted += new AsyncCompletedEventHandler(Event_DownloadFileCompleted);
  Client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(Event_DownloadProgress);
  Client.DownloadFileAsync(u, @saveTo);
}
 
public virtual void Event_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
}
}

class DownLoadFile : Internet
{
private string FileName;
private string Sup;
public DownLoadFile(string Sup_,string FileName_)
{
  if (FileName_.Trim() != "" || Sup_.Trim()!="")
  {
     FileName = FileName_;
     Sup = Sup_;
  }
  else { return; }
}
public override void Event_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
  base.Event_DownloadFileCompleted(sender, e);
  if (e.Error != null)
    {
    }
  else
    {
       //Обрабатываем скачанный файл
     }
}
}

DownLoadFile df = new DownLoadFile("name", "путь где будет файл");
df1.fileDownloadThread("ссылка", "куда сохранять");