public async Task <TEntity> GetByIdAsync(int id, IBaseSpecifications <TEntity> baseSpecifications = null)
{
try
{
var item = await _blogContext.Set <TEntity>()
.Where(x => x.Id == id)
.AsNoTracking()
.FirstOrDefaultAsync();
//var item = await SpecificationEvaluator<TEntity>.GetQuery(_blogContext.Set<TEntity>()
// .Where(x => x.Id == id)
// .AsQueryable(), baseSpecifications)
// .AsNoTracking()
// .FirstOrDefaultAsync();
// var item = await _blogContext.Set<TEntity>().Where(x => x.Id == id).AsNoTracking().FirstOrDefaultAsync();
if (item == null)
{
throw new Exception($"Couldn't find entity with id={id}");
}
return(item);
}
catch (Exception ex)
{
throw new Exception($"Couldn't retrieve entity with id={id}: {ex.Message}");
}
}
public static IQueryable <TEntity> GetQuery(IQueryable <TEntity> query, IBaseSpecifications <TEntity> specifications)
{
// Do not apply anything if specifications is null
if (specifications == null)
{
return(query);
}
// Modify the IQueryable
// Apply filter conditions
if (specifications.FilterCondition != null)
{
query = query.Where(specifications.FilterCondition);
}
// Includes
query = specifications.Includes
.Aggregate(query, (current, include) => current.Include(include));
// Apply ordering
if (specifications.OrderBy != null)
{
query = query.OrderBy(specifications.OrderBy);
}
else if (specifications.OrderByDescending != null)
{
query = query.OrderByDescending(specifications.OrderByDescending);
}
// Apply GroupBy
if (specifications.GroupBy != null)
{
query = query.GroupBy(specifications.GroupBy).SelectMany(x => x);
}
return(query);
}
