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Now, that we have our generic
base repository class,

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let's update our comic books and
comic book artists repositories to use it.

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First, let's update the comic
books repository class.

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To start inherit from
the base repository class,

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specifying comic book for
the T entity generic type parameter.

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Colon, BaseRepository<ComicBook> and
we get build errors.

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The error in the class is telling us that
we didn't implement the abstract get and

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getList methods.

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We'll get to that in just a bit.

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For now, let's move on to
the error with the constructor.

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There is no argument given that
corresponds to the required

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formal parameter context of base
repository of type ComicBook,

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base repository context.

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The constructive for the base class
require us the pass in a context instance.

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To do that we can use the base keyword in
order to call the base class constructor

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and pass in the context parameter that is
being passed to the ComicBook Repository

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constructor :base(context),
then pass in the context parameter.

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We no longer need
the context private field,

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as we'll use the context
property in the base class.

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The green squiggle under
the getlist method name

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is telling us that our method is hiding
the inherited method of the same name.

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This error is easy to fix.

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We just need to add the override
keyword to make our intentions clear to

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the compiler.

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public, override, and
do the same for the Get method.

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Public, override.

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We also need to remove the add,
update, and delete methods.

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That might seem counter-intuitive but
remember,

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the base repository class is providing
the implementations for these methods.

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To resolve the remaining errors,
we need to replace all references to

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the _context private field with
the base class's Context property.

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Now, let's finish up by updating
the ComicBookArtistsRepository class.

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Inherit from the BaseRepository class,

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specify ComicBookArtist for
the T entity generic type parameter,

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update the constructor to call
the base class constructor.

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And remove the context private field.

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The signature for the get method currently
doesn't match the base classes get method.

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If we put our cursor on the class name and
press control period or

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dot, we can select to
implement the abstract class.

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Which will add overrides for
the missing methods, then we can cut and

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paste the old get method implementation
down into the new get method.

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And remove the old get add and
delete methods.

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The new get method supports the ability
for the caller to specify whether or

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not the related entities are included or
not.

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So, we need to update our
method implementation

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to respect that parameter value.

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To start, let's call the AsQueryable
method on the ComicBookArtists DB

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set property in order to
get a IQueryable object.

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Var comicBookArtist equals

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Context.ComicBookArtists.AsQueryable.

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Then, let's add a conditional statement
that checks if the include related

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entities parameter is set to true.

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If include related entities, and
within the if statement code block we can

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add the calls to the include method
to eagerly load the related entities.

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ComicBookArtists equals comicBookArtists.

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Then, cut and
paste the include method calls to there.

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Then finish up with returning the result
of a query to retrieve the comicBookArtist

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with the passed in ID parameter value.

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Looks like we can just modify
this to suit our purposes.

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Return comicBookArtists where
cba goes to cba.Id == id and

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then calling SingleOrDefault.

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The original version of
the repository didn't include a method

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to get a collection of comic book artists.

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But the base class requires us to
override its abstract getList method.

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Since our web app doesn't need a method
to get a list of comic book artists,

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we can just leave the step-out
method that throws a new instance of

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the NotImplementedException class and
that's it.

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Now, let's run and test our web app.

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Here is our list of Comic Books,

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let's add a new Comic Book Bone and
then issue number 5.

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Jeff Smith for the artist and
script for the role.

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Here's the detail for that new issue,
let's add another artist.

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Jeff Smith again,
this time pencils for the role.

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Here's that new artist in his role,
let's delete that artist

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And delete the comic book.

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Looks like everything's
still works as expected.