1.参考文档说修改项目文件添加,就得这么做,不然会报错
<ItemGroup>
<DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="2.0.0" />
</ItemGroup>
https://www.cnblogs.com/Starts_2000/p/mysql-efcore20-codefirst-dbfirst-migration-demo.html
2.跨域问题
https://www.cnblogs.com/tianma3798/p/6940794.html
3.仓库模式
https://www.cnblogs.com/zhijianliutang/archive/2012/02/24/2367305.html
原文：https://www.cnblogs.com/xinzhyu/p/8969811.html