public FetchPagingParameters(FetchParameters <TModel> model) : base(model)
{
PagingRule = new PagingRule()
{
PageIndex = 1, PageSize = int.MaxValue
};
}
public FetchParameters <TModel> SetPaging(int pageIndex, int pageSize)
{
PagingRule = new PagingRule()
{
PageIndex = pageIndex, PageSize = pageSize
};
return(this);
}
internal PagingResult <TModel> Paging <TModel>(IQueryable <TModel> items, PagingRule paging) where TModel : class
{
var total = 0;
var result = FormPagingQuery(items, paging, out total).ToList();
var res = new PagingResult <TModel>()
{
Items = result,
PageIndex = paging.PageIndex,
PageSize = paging.PageSize,
TotalItemsCount = total
};
if (res.Items == null)
{
// just in case
res.Items = new List <TModel>();
}
return(res);
}
public IPagingFetchBuilder <TModel> SetPaging(PagingRule pagingRule)
{
fetchParameters.SetPaging(pagingRule.PageIndex, pagingRule.PageSize);
return(this);
}
// TODO: doublecheck deadlocks
internal async Task <PagingResult <TModel> > PagingAsync <TModel>(IQueryable <TModel> items, PagingRule paging) where TModel : class
{
var total = 0;
var result = await FormPagingQuery(items, paging, out total).ToListAsync().ConfigureAwait(false);
var res = new PagingResult <TModel>()
{
Items = result,
PageIndex = paging.PageIndex,
PageSize = paging.PageSize,
TotalItemsCount = total
};
if (res.Items == null)
{
// just in case
res.Items = new List <TModel>();
}
return(res);
}
private IQueryable <TModel> FormPagingQuery <TModel>(IQueryable <TModel> items, PagingRule paging, out int total)
where TModel : class
{
Check.NotNull(items, "items");
total = items.Count();
// unload everything if paging not defined.
paging.PageSize = paging.PageSize <= 0 ?
total
: paging.PageSize;
if ((paging.PageIndex - 1) * paging.PageSize >= total)
{
paging.PageSize = paging.PageSize == 0 ? int.MaxValue : paging.PageSize;
paging.PageIndex = (total / paging.PageSize) - 1;
}
if (paging.PageIndex <= 0)
{
paging.PageIndex = 1;
}
var result = items
.Skip(paging.PageSize * (paging.PageIndex - 1))
.Take(paging.PageSize);
return(result);
}
public Task <PagingResult <TModel> > PagingAsync(IQueryable <TModel> items, PagingRule paging)
{
return(repository.PagingAsync(items, paging));
}