DateDiff() function in C#

By Fons Sonnemans, posted on
5601 Views 4 Comments

I have written the following DateDiff() function in C#. VB.NET users already had it using the Micrsoft.VisualBasic.dll assembly. Now you can use it without referencing this 'ugly' extra assembly.

using System;


namespace ReflectionIT.System {

   &nbsppublicenum DateInterval {
   &nbsp   &nbspYear,
   &nbsp   &nbspMonth,
   &nbsp   &nbspWeekday,
   &nbsp   &nbspDay,
   &nbsp   &nbspHour,
   &nbsp   &nbspMinute,
   &nbsp   &nbspSecond
   &nbsp}

   &nbsppublicclass DateTimeUtil {

   &nbsp   &nbsppublicstaticlong DateDiff(DateInterval interval, DateTime date1, DateTime date2){

   &nbsp   &nbsp   &nbspTimeSpan ts=date2-date1;

   &nbsp   &nbsp   &nbspswitch(interval){
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Year:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturndate2.Year -date1.Year;
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Month:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn(date2.Month -date1.Month)+(12*(date2.Year -date1.Year));
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Weekday:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn Fix(ts.TotalDays)/7;
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Day:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn Fix(ts.TotalDays);
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Hour:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn Fix(ts.TotalHours);
   &nbsp   &nbsp   &nbsp   &nbspcase DateInterval.Minute:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn Fix(ts.TotalMinutes);
   &nbsp   &nbsp   &nbsp   &nbspdefault:
   &nbsp   &nbsp   &nbsp   &nbsp   &nbspreturn Fix(ts.TotalSeconds);
   &nbsp   &nbsp   &nbsp}
   &nbsp   &nbsp}

   &nbsp   &nbspprivatestaticlong Fix(double Number){
   &nbsp   &nbsp   &nbspif(Number >=0){
   &nbsp   &nbsp   &nbsp   &nbspreturn(long)Math.Floor(Number);
   &nbsp   &nbsp   &nbsp}
   &nbsp   &nbsp   &nbspreturn(long)Math.Ceiling(Number);
   &nbsp   &nbsp}
   &nbsp}
}


All postings/content on this blog are provided "AS IS" with no warranties, and confer no rights. All entries in this blog are my opinion and don't necessarily reflect the opinion of my employer or sponsors. The content on this site is licensed under a Creative Commons Attribution By license.

Leave a comment

Blog comments

Raj

06-May-2013 8:48
If you want the exact DateDiff function as it works in SQL, you can remove time stamp of the Date variables and then Subtract one from another. It will give u exact number of days. Ex. DateTime dt = DateTime.Parse(fromDate.ToShortDateString()); DateTime dt1 = DateTime.Parse(toDate.ToShortDateString()); int noOfDays = dt.Subtract(dt1).TotalDays;

Marco Pellicciotta

13-Nov-2013 4:35
Exactly what I was looking for. Thanks!

Marco Pellicciotta

13-Nov-2013 4:46
The trick is with month values, because TimeSpan do not give you the difference of months.

Marco Pellicciotta

30-Jan-2014 8:32
Marco Pellicciotta: After using it a few times a see a bug and I want to report. The fix function must be: private static long Fix(double Number) { if (Number >= 0) { return (long)Math.Ceiling(Number); } return (long)Math.Floor(Number); } } Just change Ceiling by Floor.