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POWhy do I not get the "Cross-thread operation not valid" error
 

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  1. POWhy do I not get the "Cross-thread operation not valid" error
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    <p>I use a BackgroundWorker and do this:</p> <pre><code>private void loadNewAsyncToolStripMenuItem_Click(object sender, EventArgs e) { this.Text = "RunWorkerAsync()"; backgroundWorkerLoading.RunWorkerAsync(); } private void backgroundWorkerLoading_DoWork(object sender, DoWorkEventArgs e) { UnsafeThreadMethod("hello"); EvenUnsaferThreadMethod(); } </code></pre> <p>And now the two methods.</p> <pre><code>private void UnsafeThreadMethod(string text) { toolStripLabelRssFeedData.Text = text; } private void EvenUnsaferThreadMethod() { panelLoading.Visible = true; } </code></pre> <p>I don't understand why <code>UnsafeThreadMethod</code> doesn't throw the following exception but <code>EvenUnsaferThreadMethod</code> does.</p> <blockquote> <p>Cross-thread operation not valid: Control 'panelLoading' accessed from a thread other than the > thread it was created on.</p> </blockquote> <p>According to the message it's because <code>toolStripLabelRssFeedData</code> was created on the same thread but it wasn't.</p> <p>I thought that I can't call controls created by the main thread and have to use the <code>ProgressChanged</code> event. What's going on?</p> <p>And I have a second question. What is the advantage of doing it like this when I can use <code>ProgressChanged</code>? What should I do?</p> <pre><code>private void EvenUnsaferThreadMethod() { if (panelLoading.InvokeRequired) { panelLoading.Invoke(new MethodInvoker(() =&gt; { EvenUnsaferThreadMethod(); })); } else { panelLoading.Visible = true; } } </code></pre>
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