When using Scaffold-DbContext for UWP I get 'U

问题:

I am trying to scaffolf an Entityframeworkcore DbContext for a UWP app from a Sqlite databse. I do:

Scaffold-DbContext "data source=C:\SqliteDbFiles\Sqlite.db" Microsoft.EntityFrameworkCore.Sqlite

No matter what I try though I keep getting this error:

System.DllNotFoundException: Unable to load DLL 'sqlite3': This operation is only valid in the context of an app container. (Exception from HRESULT: 0x8007109A)
   at Microsoft.Data.Sqlite.Interop.NativeMethods.Sqlite3_sqlite3.sqlite3_open_v2(IntPtr filename, Sqlite3Handle& ppDb, Int32 flags, IntPtr vfs)
   at Microsoft.Data.Sqlite.Interop.NativeMethods.Sqlite3_sqlite3.open_v2(IntPtr filename, Sqlite3Handle& ppDb, Int32 flags, IntPtr vfs)
   at Microsoft.Data.Sqlite.Interop.NativeMethods.sqlite3_open_v2(String filename, Sqlite3Handle& ppDb, Int32 flags, String vfs)
   at Microsoft.Data.Sqlite.SqliteConnection.Open()
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.SqliteDatabaseModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.RelationalScaffoldingModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.SqliteScaffoldingModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.ReverseEngineeringGenerator.GetMetadataModel(ReverseEngineeringConfiguration configuration)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.ReverseEngineeringGenerator.GenerateAsync(ReverseEngineeringConfiguration configuration, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Design.DatabaseOperations.ReverseEngineerAsync(String provider, String connectionString, String outputDir, String dbContextClassName, IEnumerable`1 schemas, IEnumerable`1 tables, Boolean useDataAnnotations, Boolean overwriteFiles, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.<ReverseEngineerImpl>d__21.MoveNext()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass4_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Unable to load DLL 'sqlite3': This operation is only valid in the context of an app container. (Exception from HRESULT: 0x8007109A)

Any help would be greatly appreciated

回答1:

The version of sqlite3.dll used at runtime on UWP won't work at design-time. You can manually download one of the Precompiled Binaries for Windows and copy it to the output directory (e.g. bin\x86\Debug) before running the command.

A simpler solution might be to scaffold the DbContext in a non-UWP project and just copy the classes into the UWP project after they're generated.