简单实现记事本的功能，可以设置背景颜色，设置字体大小，字体倾斜，加粗，但是无法实现字体改变。可以实现查找字符功能-Simple implementation of the notebook features, you can set the background color, set the font size, font tilt, bold, but can not realize the font change. Function can find the character