我正在开发一个 MVC 5 应用程序。在我的 MVC 5 应用程序中，我想从 App-Data 文件夹创建一个 mdf 文件，但是当我想从 Add_Data 文件夹的添加新项目菜单中添加 mdf 文件时，我收到一个错误
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 50 – Local Database Runtime error occurred. Cannot create an automatic instance. See the Windows Application event log for error details