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C# Entity Framework Basics Entity Framework and Databases Changing the Database Name

Dmitri Mikhalev
Dmitri Mikhalev
4,462 Points
Posted by Dmitri Mikhalev
Dmitri Mikhalev
4,462 Points

SystemArgumentException

When trying to create the database with the AppConfig option, I get this error in Program.cs:

"System.ArgumentException HResult=0x80070057 Message=The ADO.NET provider with invariant name 'Sql.Data.SqlClient' is either not registered in the machine or application config file, or could not be loaded. See the inner exception for details. Source=EntityFramework StackTrace:[...]"

it pops up next to "context" at the bottom, in this part of the code:

context.ComicBooks.Add(new ComicBook()
                {
                    SeriesTitle = "The Amazing Spider-Man",
                    IssueNumber = 1,
                    PublishedOn = DateTime.Today
                });
                context.SaveChanges();

Why is that?

2 Answers

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

Due to "lazy loading", that's probably the first point in the program where an attempt is made to contact the database.

Since the connection information was just moved to the app.config file in this lesson, I'd look there for a possible typo in the connectionString or providerName.

Dmitri Mikhalev
Dmitri Mikhalev
4,462 Points
Dmitri Mikhalev
Dmitri Mikhalev
4,462 Points

I found it later on... thanks for your help!