public static void PopulateDatabase(OptionalBlogsContext context)
{
using (context)
{
context.Add(
new Blog
{
Name = ".NET Blog",
Posts =
{
new Post
{
Title = "Announcing the Release of EF Core 5.0",
Content = "Announcing the release of EF Core 5.0, a full featured cross-platform..."
},
new Post
{
Title = "Announcing F# 5",
Content = "F# 5 is the latest version of F#, the functional programming language..."
},
}
});
context.SaveChanges();
}
}
public static void RecreateCleanDatabase(OptionalBlogsContext context)
{
using (context)
{
context.Database.EnsureDeleted();
context.Database.EnsureCreated();
}
}
public static Dictionary <DeleteBehavior, string> GatherData(Action <OptionalBlogsContext> action)
{
var results = new Dictionary <DeleteBehavior, string>();
foreach (var deleteBehavior in DeleteBehaviors)
{
RecreateCleanDatabase(new OptionalBlogsContext(deleteBehavior));
PopulateDatabase(new OptionalBlogsContext(deleteBehavior));
try
{
using var context = new OptionalBlogsContext(deleteBehavior);
action(context);
context.ChangeTracker.DetectChanges();
var deletingPosts = context.ChangeTracker.Entries <Post>().Any(e => e.State == EntityState.Deleted);
var settingFksToNull = context.ChangeTracker.Entries <Post>().Any(e => e.State == EntityState.Modified);
context.SaveChanges();
var deletedPosts = !context.Posts.AsNoTracking().Any();
results[deleteBehavior] =
deletingPosts
? "Dependents deleted by EF Core"
: deletedPosts
? "Dependents deleted by database"
: settingFksToNull
? "Dependent FKs set to null by EF Core"
: "Dependent FKs set to null by database";
}
catch (Exception e)
{
results[deleteBehavior] = $"`{e.GetType().Name}`";
}
}
return(results);
}