How to make a thread wait until another thread finishes?

Form opens before all data is fetched. How to make UI thread wait for first cycle of the processing thread to finish?

• My application fetches data from a live feed, processes it and displays the results. This data is updated every 5 seconds. In the Load event of Main form I've created a thread to show the splash screen which is shown until the first data cycle is run . The data fetching and processing thread (RecieverThread) calls RecieveFeed. The isue I'm facing is that form2 which displays data fetched in RecieveFeed is shown before the first cycle is run completely. How do I ensure that form2 is loaded only after the first cycle has completed fetching data. Code in the Main form: private void frmMain_Load(object sender, EventArgs e) { Hide(); // Create a new thread from which to start the splash screen form Thread splashThread = new Thread(new ThreadStart(StartSplash)); splashThread.Start(); //Thread to call the live feed engine. This thread will run for the duration of application ReceiverThread = new System.Threading.Thread(new System.Threading.ThreadStart(ReceiveFeed)); ReceiverThread.Start(); frmSecondForm form2 = new frmSecondForm(); form2.MdiParent = this; form2.WindowState = FormWindowState.Maximized; Show(); form2.Show(); } public frmRaceRace() { InitializeComponent(); this.splash = new SplashScreen(); } private void StartSplash() { splash.Show(); while (!done) { Application.DoEvents(); } splash.Close(); this.splash.Dispose(); } private void ReceiveFeed() { while (!StopReceivingData) { foreach (...) { //Fetches data from live engine DLLImportClass.GetData1(); //Manipulates and stores the data fetched in datatables ThreadPool.QueueUserWorkItem(new WaitCallback(delegate { StoreData(); })) rowsProcessed++; if (!done) { this.splash.UpdateProgress(100 * rowsProcessed / totalRows); } } done = true; Thread.Sleep(5000); } }

• Answer:

  I think what you need to use here is System.Threading.AutoResetEvent. Basically, add a member of this to your form class: private AutoResetEvent waitEvent_ = new AutoResetEvent(false); // create unininitialized After showing your splash, you want to wait for this event to be signalled: private void StartSplash() { splash.Show(); // this will time out after 10 seconds. Use WaitOne() to wait indefinitely. if(waitEvent_.WaitOne(10000)) { // WaitOne() returns true if the event was signalled. } } // eo StartSplash Finally, in your processing function, when you're done, simply call: waitEvent_.Set();