Graphics.FillRectangle() didn't work
<pre><code>Graphics gp = Graphics.FromHwnd(p2pPic.Handle);

SolidBrush sb = new SolidBrush(Color.DodgerBlue);

lock (gpPalette)
{
     gpP.FillRectangle(sb, aRectangle);
}
</code></pre>

<p><code>p2pPic</code> is a <code>PictureBox</code> object in c#;
these are the main code ,and code does run, but did not take any effect who can tell me why?</p>
