学习

https://blog.csdn.net/harmsworth2016/article/details/79600352   ---> 实现面板拖动放大

https://blog.csdn.net/qq_29436563/article/details/79994388 --->实现面板点击之外关闭

https://www.jb51.net/article/135795.htm  // 裁剪图片

https://blog.csdn.net/guozhangqiang/article/details/82251893// vue点击图片预览放大（可旋转、翻转、缩放、上下切换、键盘操作）