DateTimeHelper

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Core {

    public static class DateTimeHelper {
        public static DateTime NextMonth(DateTime d) {
            return d.AddMonths(1);
        }
        public static DateTime FirstDayOfMonth(DateTime d) {
            return DateTime.Parse("{0}/1/{1}".FormatString(d.Month,d.Year));
        }
        public static DateTime LastDayOfMonth(DateTime d) {
            return FirstDayOfMonth(d).AddMonths(1).AddDays(-1);
        }
        public static DateTime ConvertFromUnixTimestamp(double timestamp) {
            DateTime origin = new DateTime(1970,1,1,0,0,0,0);
            return origin.AddSeconds(timestamp);
        }
        public static double ConvertToUnixTimestamp(DateTime date) {
            DateTime origin = new DateTime(1970,1,1,0,0,0,0);
            TimeSpan diff = date - origin;
            return Math.Floor(diff.TotalSeconds);
        }
    }
}