.net 连接数据库提示"The requested database LocalMySqlServer does not have provider name set in the connection string."

最近用.net程序连接SqlServer时，总是报“The requested database LocalMySqlServer does not have provider name set in the connection string.”,

经检查，程序配置文件内连接串格式完全正确。也未发现有"LocalMySqlServer"字样的连接串。

分析.net 找配置文件的顺序，肯定是优先找machine.config内的配置了（注：此文件的位置C:\WINNT\Microsoft.NET\Framework内对应版本的 Config子目录内）。

于是找开machine.config，果然发现：

<connectionStrings>
<add name="LocalSqlServer" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient" />
<add name="LocalMySqlServer" connectionString="" />
</connectionStrings>

 对上述配置项进行注释后，程序启动正常

.net 连接数据库提示"The requested database LocalMySqlServer does not have provider name set in the connection string."

原文：https://www.cnblogs.com/todayhero/p/11229847.html