sqflite插件简单使用 key======================

 https://blog.csdn.net/weixin_34183910/article/details/86029912

https://blog.csdn.net/u013255127/article/details/88018997

https://www.jb51.net/article/157694.htm

 

read and write file to storage card

https://grokonez.com/flutter/flutter-read-write-file-example-path-provider-dartio-example