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    <p>I believe BackgroundWorker is designed to automatically utilize a new thread. Therefore creating a new thread just to call RunWorkerAsync is redundant. You are creating a thread just to create yet another thread. What's probably happening is this:</p> <ol> <li>You create a new thread from thread 1 (the GUI thread); call this thread 2.</li> <li>From thread 2, you launch RunWorkerAsync which itself creates yet another thread; call this thread 3.</li> <li>The code for RunWorkerCompleted runs on thread 2, which is the thread that called RunWorkerAsync.</li> <li>Since thread 2 is not the same as the GUI thread (thread 1), you get an illegal cross-thread call exception.</li> </ol> <p>(The below suggestion uses VB instead of C# since that's what I'm more familiar with; I'm guessing you can figure out how to write the appropriate C# code to do the same thing.)</p> <p>Get rid of the extraneous new thread; just declare _worker WithEvents, add handlers to _worker.DoWork and _worker.RunWorkerCompleted, and then call _worker.RunWorkerAsync instead of defining a custom PerformWorkerTask function.</p> <p><strong>EDIT</strong>: To update GUI controls in a thread-safe manner, use code like the following (more or less copied from <a href="http://msdn.microsoft.com/en-us/library/ms171728.aspx" rel="nofollow noreferrer">this article from MSDN</a>):</p> <pre><code>delegate void SetTextCallback(System.Windows.Forms.Control c, string t); private void SafeSetText(System.Windows.Forms.Control c, string t) { if (c.InvokeRequired) { SetTextCallback d = new SetTextCallback(SafeSetText); d.Invoke(d, new object[] { c, t }); } else { c.Text = t; } } </code></pre>
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    1. USDan Tao
    1. USDan Tao
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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