Here is my situation. Im trying to learn how to take full advantage of multithreading but am at a rump.

I have one listbox of usernames and it checks them on a website to see if they exist or not. If they exist it puts the username into listbox2.

Now that portion works fine. But im wondering how i can use say 5 threads to go through the list and check the names quicker. My code is as follows:

//Start
        public void button5_Click(object sender, EventArgs e)
        {
            try
            {
                for (int i = 0; i < 1; i++)
                {

                   // listBox1.SelectedIndex = i;
                    Thread thread1 = new Thread(new ThreadStart(this.getSite));
                    thread1.Start();
                    while (thread1.IsAlive)
                    {
                        Application.DoEvents();
                   
                    }
                    if(!(thread1.IsAlive))
                    {
                     label2.Text = "Count: " + listBox2.Items.Count;
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }

        }

        public void getSite()
        {
            for (int j = 0; j < listBox1.Items.Count; j++)
            {

                string uri = @"http://www.website.com";
                string username = listBox1.Items[j].ToString();
                string data = "accountName=" + username;
                string source = "";

                source = getInfo(data, uri);

                if (source.Contains("nswer"))
                {
                    listBox2.Invoke(new UpdateTextCallback(this.addUsername), new object[] { username });
                }

            }
        }// END GET SITE

        //Used to invoke username into listbox2 
        public void addUsername(string user)
        {
            // Add the listbox text
            listBox2.Items.Add(user);
        }
      
        //Used to invoke username into listbox2 
        public delegate void UpdateTextCallback(string user);

        public static string getInfo(string DATA, string URL)
        {
            HttpWebRequest req = (HttpWebRequest)System.Net.WebRequest.Create(URL);
            req.Method = "post";
            req.ContentType = "application/x-www-form-urlencoded";
            req.AllowAutoRedirect = true;

            // Encode data and post it 
            byte[] bytes = System.Text.Encoding.ASCII.GetBytes(DATA);
            req.ContentLength = DATA.Length;
            Stream os = req.GetRequestStream();
            os.Write(bytes, 0, bytes.Length);
            os.Close();

            // Get response
            HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
            StreamReader ResponseStream = new StreamReader(resp.GetResponseStream());
            string Source = "";
            Source = ResponseStream.ReadToEnd();

            return Source;

        }

My problem is i wouldnt know how to tell it to skip the username that is being checked by another thread. Any help is greatly appreciated.

Kil the whole application doevents bit, thats a sure way to tie yourself in knots.

Have a list items you've queued up to go, fire off 5, as each of the 5 finish, take the next one off the queue and start a new thread. until you have nothing left in the queue.

At the end of each threadrun, issue an event to say "A thread finished, heres the result" ..

As you PMd me to say you'd solved, this, please mark this thread as solved.

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