How to add entity-framework to console application (images are included)

问题

I try to add entity-framework to console application: I press "add new item" and

then

then

then I added code:

    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                Database1Entities db = new Database1Entities();
                db.AddToTableTest(new TableTest { name = "name" });
                db.SaveChanges();

                int count = db.TableTest.Count();
                int ui = 9 + 0;
            }
            catch (Exception e)
            {

            }
        }
    }

It gives no error, but I don't see any changes in database. I described the issue better here

回答1:

I did the same steps you did to setup a EF model. your database.mdf file has the Copy to Output Directory set to Copy always, that means that every time you hit F5 (build or debug your app) the file is getting replaced by the empty one on your project.

Changing the Copy to Output Directory on the Properties window of the mdf file should solve your problem.

If you use Copy if newer you are going to be persisting any modifications on the contents of the database until you edit the database (mdf) itself.

With Do not copy any change to the mdf file is not going to get reflected on your application and will probably generate problems with EF.

I recommend for this scenario that you use Copy if newer and fill your basic data in the mdf file so you will have it always available.

来源：https://stackoverflow.com/questions/13385013/how-to-add-entity-framework-to-console-application-images-are-included