Eager loading of multiple related entities
I need to add an extension method that can handle multiple Include to an already existing Repository class:
public abstract class Repository<TEntity, TPrimaryKey> : IRepository<TEntity, TPrimaryKey>
where TEntity : class
{
private MyContext _dbContext;
private readonly DbSet<TEntity> _dbSet;
public IDatabaseFactory DatabaseFactory { get; private set; }
protected Repository(IDatabaseFactory databaseFactory)
{
DatabaseFactory = databaseFactory;
_dbSet = Context.Set<TEntity>();
}
protected MyContext Context
{
get { return _dbContext ?? (_dbContext = DatabaseFactory.Get()); }
}
public IQueryable<TEntity> Include(Expression<Func<TEntity, object>> path)
{
return _dbSet.Include(path);
}
}
The current implementation can only handle one related entity. I need to be able to eager load two or more related entites as well.
my entity class:
public class Employee
{
public int EmployeeId { get; set; }
public virtual ICollection<Adjustment> Adjustments { get; set; }
public int? TotalAdjustmentsPerEmployeeId { get; set; }
public virtual TotalAdjustmentsPerEmployee TotalAdjustmentPerEmployee { get; set; }
}
Where I will use it:
public class 开发者_StackOverflowEmployeeRepository : Repository<Employee, int>, IEmployeeRepository
{
public EmployeeRepository(IDatabaseFactory databaseFactory) : base(databaseFactory)
{ }
public IEnumerable<Employee> GetAll(int companyID)
{
/**
* I need to load employees based on their companyID and eager load
* related TotalAdjustmentPerEmployee and Adjustments entities something like:
* return this.Include(a => a.TotalAdjustmentPerEmployee)
* .Include(a => a.Adjustments)
* .Where(e => e.CompanyId == companyID);
*/
}
}
Thank you!
The simplest way I can think of would be to use a param array:
public IQueryable<TEntity> Include<TInclude>(params Expression<Func<TEntity, TInclude>>[] paths)
{
IQueryable<TEntity> results = _dbset;
paths.ToList().ForEach(x => results = results.Include(x));
return results
}
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