一个edit类，实现控件的只读操作等，适合初学者-Edit a class that implements the control of a read-only operation, suitable for beginners

MFC自绘编辑框类,自绘了编辑的边框的大小和颜色以及禁止时的效果-MFC edit box class self-drawn, painted the edit border size and color and effect when disabled