C#

if (behavior.IsVisible)
{
                Show();
                mImage = new Bitmap(Width, Height);
                Graphics dc = Graphics.FromHwnd(Handle);
                dc.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixelGridFit;
                SizeF size = dc.MeasureString(behavior.DisplayText, behavior.Font);
                dc.Dispose();

                Height = (int)size.Height + 1;
                Width = (int)size.Width + 1;
                mImage = new Bitmap(Width, Height);
                dc = Graphics.FromImage(mImage);
                dc.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixelGridFit;

                Color background = (behavior.Color.ToArgb() == Color.White.ToArgb()) ? Color.Black : Color.White;
                dc.Clear(background);

                dc.DrawString(behavior.DisplayText, behavior.Font, new SolidBrush(behavior.Color), 0, 0);
                mTextColor = behavior.Color.ToArgb();

                dc.Dispose();

                BackgroundImage = mImage;
                TransparencyKey = background;
}
else
{
                Hide();
                BackgroundImage = null;
}