public static async Task <Page <T> > GetPage <T>(this IQueryable <T> source, PaginationCriteriaBase criteria)
{
var page = await GetPageBase <Page <T>, T>(source, criteria);
page.Total = await source.CountAsync();
return(page);
}
public static Task <SimplePage <T> > GetSimplePage <T>(
this IQueryable <T> source, PaginationCriteriaBase criteria) => GetPageBase <SimplePage <T>, T>(source, criteria);
static async Task <TPage> GetPageBase <TPage, TItem>(IQueryable <TItem> source, PaginationCriteriaBase criteria)
where TPage : SimplePage <TItem>, new()
{
var itemsPerPage = criteria.ItemsPerPage ?? DefaultItemsPerPage;
if (itemsPerPage < 1)
{
throw new AppException($"Invalid ItemsPerPage ({criteria.ItemsPerPage})");
}
if (criteria is PaginationCriteria c)
{
source = source.Skip(itemsPerPage * c.PageNum);
}
var items = await source
.Take(itemsPerPage + 1)
.ToArrayAsync();
return(new TPage
{
Items = items.Take(itemsPerPage).ToArray(),
HasMore = items.Length > itemsPerPage
});
}