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copied!<p>So you start out by saying that you want to perform a task every X seconds. That tells us that we need a timer. There are a lot to choose from though. <code>System.Timer</code> should work fine for our purposes, but if you want to use the <code>System.Windows.Forms.Timer</code> you can. You'll want to start the timer when you open the form, configure the interval to what you want, and assign a handler to run when the timer fires.</p> <p>Next, when the timer fires you need to perform a database call and update the UI. Performing a long running operation and then updating the UI with the results is what the <code>BackgroundWorker</code> class was tailor made for. Set the <code>DoWork</code> method to do your database call, and have the <code>WorkerCompleted</code> event update the UI based on the results. (The completed event will automatically be run in the UI thread; you don't need to manually marshal to that thread.)</p> <p>You could also use Tasks to do these same things, if you have a new enough version of C#. You could use <code>Task.Factory.StartNew</code> for the database call to have it run in a background thread, and then you can call <code>ContinueWith</code> on the <code>Task</code> it returns and use the overload that allows you to specify a synchronization context. Here's a simple example:</p> <pre><code>private void handler(object sender, EventArgs e) { Task.Factory.StartNew(() => getInfoFromDB()) .ContinueWith(task => label1.Text = task.Result, CancellationToken.None, TaskContinuationOptions.None, TaskScheduler.FromCurrentSynchronizationContext()); } private string getInfoFromDB() { Thread.Sleep(2000);//simulate long IO operation return "Hello world!"; } </code></pre> <p>Note that for this <code>Task</code> based example to work you would need to use the <code>System.Windows.Forms.Timer</code> timer, so that the tick event runs in the UI thread.</p>

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