Callum Linington Callum Linington - 15 days ago 5
C# Question

EntityFramework Eager Load all Navigation Properties

I'm using the Repository pattern with DI and IoC.

I have created a function in my Repository:

T EagerGetById<T>(Guid id, string include) where T : class
{
return _dbContext.Set<T>().Include(include).Find(id);
}


This will eagerly load one navigation property in my entity right.

But if my entity looks like this:

public class Blog : PrimaryKey
{
public Author Author {get;set;}
public ICollection<Post> Posts {get;set;}
}


How would I get eager loading for
Author
and
Posts
? Would I literally have to do:

_dbContext.Set<T>().Include("Author").Include("Posts").Find(id);


inevitably producing a function like this:

T EagerGetById<T>(Guid id, string include, string include2, string include3) where T : class
{
return _dbContext.Set<T>().Include(include).Include(include2).Include(include3).Find(id);
}


Because that would be really inefficient for a
Generic
Repository!

Answer

If you don't want to use strings, you can also do the same for any N number of includes by using an expression which returns the navigation properties to be eager loaded. (original source here)

public IQueryable<TEntity> GetAllIncluding(params Expression<Func<TEntity, object>>[] includeProperties) 
{
   IQueryable<TEntity> queryable = GetAll();
   foreach (Expression<Func<TEntity, object>> includeProperty in includeProperties) 
   {
      queryable = queryable.Include<TEntity, object>(includeProperty);
   }

   return queryable;
}