public async static Task <PagedList <TProjection> > ToPagedListAsync <TProjection>(this IAggregateFluent <TProjection> findFluent, int pageNumber, int pageSize)
{
var count = await findFluent.AnyAsync() ? findFluent.Group(new BsonDocument
{
{ "_id", "_id" },
{ "count", new BsonDocument("$sum", 1) }
})
.FirstAsync().Result["count"].AsInt32 : 0;
var items = await findFluent.Skip(pageSize *(pageNumber - 1))
.Limit(pageSize)
.ToListAsync();
return(new PagedList <TProjection>(items, count, pageNumber, pageSize));
}