咦，代码块怎么不管用了
public class dbpicture:System.Windows.Forms.PictureBox
    {
       public dbpicture()
        {
            SetStyle(System.Windows.Forms.ControlStyles.DoubleBuffer | System.Windows.Forms.ControlStyles.OptimizedDoubleBuffer | System.Windows.Forms.ControlStyles.AllPaintingInWmPaint, true);
            UpdateStyles();
        }
    }