public static async Task <PagedQueryResult <TEntity> > PagedQueryAsync <TEntity, TOrderKey>(
this IQueryable <TEntity> queryable,
int page, int limit,
Expression <Func <TEntity, bool> > where = null, OrderCondition <TEntity, TOrderKey> orderBy = null)
where TEntity : class
{
return(await queryable.PagedQueryAsync <TEntity, TOrderKey, object>(page, limit, where, orderBy));
}
public static Task <PagedQueryResult <TEntity> > PagedQueryAsync <TEntity, TOrderKey, TThenOrderKey1,
TThenOrderKey2>(
this IQueryable <TEntity> queryable,
int page, int limit,
Expression <Func <TEntity, bool> > where = null, OrderCondition <TEntity, TOrderKey> orderBy = null,
OrderCondition <TEntity, TThenOrderKey1> thenBy1 = null,
OrderCondition <TEntity, TThenOrderKey2> thenBy2 = null)
where TEntity : class
{
var result = new PagedQueryResult <TEntity>();
page = page < 1 ? 1 : page;
limit = limit < 1 ? 1 : limit;
var entities = where == null ? queryable : queryable.Where(where);
if (orderBy != null)
{
entities = !orderBy.Desc
? entities.OrderBy(orderBy.Expression)
: entities.OrderByDescending(orderBy.Expression);
}
if (thenBy1 != null)
{
if (orderBy == null)
{
throw new ArgumentException("Order by should not be null when use then by");
}
entities = !thenBy1.Desc
? ((IOrderedQueryable <TEntity>)entities).ThenBy(thenBy1.Expression)
: ((IOrderedQueryable <TEntity>)entities).OrderByDescending(thenBy1.Expression);
}
if (thenBy2 != null)
{
if (orderBy == null)
{
throw new ArgumentException("Order by should not be null when use then by");
}
entities = !thenBy2.Desc
? ((IOrderedQueryable <TEntity>)entities).ThenBy(thenBy2.Expression)
: ((IOrderedQueryable <TEntity>)entities).OrderByDescending(thenBy2.Expression);
}
result.Count = entities.Count();
result.Page = page;
result.Limit = limit;
entities = entities.Skip((result.Page - 1) * result.Limit).Take(result.Limit);
result.Data = result.Count == 0 ? new List <TEntity>() : entities.ToList();
return(Task.FromResult(result));
}