Background Worker is not stopping

Question

I have an application with a background worker. In the doWork method i do a html web request. If this request failed (eg error 404), i want to exit from the thread before it finishes. So in my catch i added this code

 worker.CancelAsync();
    if (worker.CancellationPending)
    {
     e.Cancel = true;
    }

The problem is that the thread does not stop, but it creates a new html web request.

Some code:

try
{
var request = (HttpWebRequest)WebRequest.Create(url1);
request.Timeout = 5000;
request.UserAgent = @"Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.5) Gecko/20091102 Firefox/3.5.5";
var document = new HtmlAgilityPack.HtmlDocument();
try
{
using (var responseStream = request.GetResponse().GetResponseStream())
{
document.Load(responseStream, Encoding.UTF8);
//some lines of code to parse html
}
catch (WebException we){
worker.CancelAsync();
if (worker.CancellationPending)
{
e.Cancel = true;
return;
}
}
catch (Exception) { }

This is my do work method...

Answer 1

You need to set worker.WorkerSupportsCancellation to true . Defualt value is false . Set the property to true before running it -

BackgroundWorker worker = new BackgroundWorker();
worker.WorkerSupportsCancellation = true;
worker.RunWorkerAsync();

Edit

Set the cancel property and return from the DoWork method -

if (worker.CancellationPending)
{
   e.Cancel = true;
   return;
}