title: Removing a window style after the window's creation
body: <p>I have created a window with the following code:</p>
  
  <pre><code>hWnd = CreateWindowEx(WS_EX_TOPMOST | WS_EX_WINDOWEDGE, szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 640, 480, NULL, NULL, hInstance, NULL);
  </code></pre>
  
  <p>The window has the <code>WS_EX_TOPMOST</code> style at the creation time, but I want to remove this style if a button is clicked. I saw <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/ms633591%28v=vs.85%29.aspx" rel="nofollow">reference for <code>SetWindowLong()</code></a> but I don't know how to use it in this situation.</p>