The Entity Framework provider type 'MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.EntityFramework, Version=8.0.18.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' registered in the application config file for the ADO.NET provider with invariant name 'MySql.Data.MySqlClient' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application. See http://go.microsoft.com/fwlink/?LinkId=260882 for more information.
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项目运行目录下缺少文件“MySql.Data.EntityFramework.dll”，从官网https://downloads.mysql.com/archives/c-net/，下载“MySQL Connector/NET (Archived Versions)”安装包，注意对齐当前mysql版本。下载安装后，在安装目录下找到MySql.Data.EntityFramework.dll，拷贝到程序目录下即可。
