protected override void OnSizeChanged(EventArgs e)
        {
            base.OnSizeChanged(e);//报错：“CsGL.OSLib”的类型初始值设定项引发异常
            Size s = this.Size;

            if (s.Height == 0)
                s.Height = 1;

            GL.glViewport(0, 0, s.Width, s.Height);

            GL.glMatrixMode(GL.GL_PROJECTION);
            GL.glLoadIdentity();
            GL.gluPerspective(45.0f, (double)s.Width / (double)s.Height, 0.1f, 100.0f);
            GL.glMatrixMode(GL.GL_MODELVIEW);
            GL.glLoadIdentity();
        }