ByArgo.cs

private IQueryable<BlogPost> FilterByCustomDateTimeCriteria(IQueryable<BlogPost> query, string sYear, string sMonth, ref int? totalCount)
    {
        var values = new List<object>();
        var filterValues = new List<object>();

        var years = sYear.Split(',');
        var months = sMonth.Split(',');

        //if the url does not contain a pair of month and year the query will not be filtered
        if (years.Count() != months.Count())
        {
            return query;
        }

        string filter = null;

        var j = 0;
        var k = 1;
        for (int i = 0; i < years.Count(); i++)
        {
            if (i > 0)
            {
                filter += "||";
                ++k;
                j = k;
                ++k;
            }

            filter += this.SetDates(years[i], months[i], null, out values, "PublicationDate", j, k);
            filterValues.AddRange(values);
        }

        if (filter == null)
        {
            return query;
        }

        query = query.Where(filter, filterValues.ToArray());

        totalCount = query.Count();
        return query;
    }