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POUI Thread .Invoke() causing handle leak?
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  1. POUI Thread .Invoke() causing handle leak?
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    copied!<p>In what circumstances would updating a UI control from a non-UI thread could cause the processes' handles to continually increase, when using a delegate and <code>.InvokeRequired</code>?</p> <p>For example:</p> <pre><code>public delegate void DelegateUIUpdate(); private void UIUpdate() { if (someControl.InvokeRequired) { someControl.Invoke(new DelegateUIUpdate(UIUpdate)); return; } // do something with someControl } </code></pre> <p>When this is called in a loop or on timer intervals, the handles for the program consistently increase.</p> <p><strong>EDIT:</strong></p> <p>If the above is commented out and amended as such:</p> <pre><code>public delegate void DelegateUIUpdate(); private void UIUpdate() { //if (someControl.InvokeRequired) //{ // someControl.Invoke(new DelegateUIUpdate(UIUpdate)); // return; //} CheckForIllegalCrossThreadCalls = false; // do something with someControl } </code></pre> <p>...then the handles <em>stop</em> incrementing, however I don't want to allow cross thread calls, of course.</p> <p><strong>EDIT 2:</strong></p> <p>Here is a sample that shows the handles increase:</p> <pre><code>Thread thread; private delegate void UpdateGUI(); bool UpdateTheGui = false; public Form1() { InitializeComponent(); thread = new Thread(new ThreadStart(MyThreadLoop)); thread.Start(); } private void MyThreadLoop() { while (true) { Thread.Sleep(500); if (UpdateTheGui) { UpdateTheGui = false; UpdateTheGuiNow(); } } } private void UpdateTheGuiNow() { if (label1.InvokeRequired) { label1.Invoke(new UpdateGUI(UpdateTheGuiNow)); return; } label1.Text = DateTime.Now.ToString("MM-dd-yyyy HH:mm:ss"); label2.Text = DateTime.Now.ToString("MM-dd-yyyy HH:mm:ss"); label3.Text = DateTime.Now.ToString("MM-dd-yyyy HH:mm:ss"); } private void btnInvoke_Click(object sender, EventArgs e) { UpdateTheGui = true; } </code></pre>
 

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