c# Web app How to get no of working days exclude weekends and public holidays

Question

Background information

Just starting out to learn C#, im trying to build a simple web app that calculate the no of working day(s) between 2 dates.

The UI of the web app

The basic logic is when the user input a date (ie 01/05/2018) and click the button.It will calculate the total number of working day (exclude weekends and public holidays).

The problem now is the calculation isnt accurate ie between 23/05/2018 & 31/05/2018 it shows 6, it should be 7 days. And it doesnt take the dates into consideration during calculation

namespace testtest
{
public partial class First : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }


    //on btn click
    protected void Button1_Click(object sender, EventArgs e)
    {


        string dt = TextBox1.Text;
        DateTime dtDDMMYYYY = ParseDate(dt);


        string dt2 = TextBox2.Text;
        DateTime dtDDMMYYYY2 = ParseDate(dt2);

       List<DateTime> list = new List<DateTime> { 
        DateTime.ParseExact("04/05/2018", "dd/MM/yyyy", 
       CultureInfo.InvariantCulture) };

        DaysLeft(dtDDMMYYYY, dtDDMMYYYY2, true, list);
    }


    public DateTime ParseDate(string date)
    {
        DateTimeFormatInfo dateFormatProvider = new DateTimeFormatInfo();
        dateFormatProvider.ShortDatePattern = "dd/MM/yyyy";
        return DateTime.Parse(date, dateFormatProvider);
    }



    public int DaysLeft(DateTime startDate, DateTime endDate, Boolean 
     excludeWeekends, List<DateTime> excludeDates)
    {


        int count = 0;
        for (DateTime index = startDate; index < endDate; index = 
        index.AddDays(1))
        {
            if (excludeWeekends && index.DayOfWeek != DayOfWeek.Sunday && 
           index.DayOfWeek != DayOfWeek.Saturday)
            {
                bool excluded = false; ;
                for (int i = 0; i < excludeDates.Count; i++)
                {
                    if (index.Date.CompareTo(excludeDates[i].Date) == 0)
                    {
                        excluded = true;
                        break;
                    }
                }

                if (!excluded)
                {
                    count++;
                }
            }
        }
        result.Text = count.ToString();
        return count;
    }


}

}

Possible duplicate of [What is a NullReferenceException, and how do I fix it?](https://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — NineBerry, May 13 '18 at 10:12
You can check this question https://stackoverflow.com/q/1617049/4771606 — Lucian Bumb, May 13 '18 at 10:16
@epiphany This declares the field, but does not assign a value to it. So the value is `null`, when the method `DaysLeft` is called. — NineBerry, May 13 '18 at 10:21
@NineBerry I've edited the code, but now the no of day is 0 no matter what dates i input — epiphany, May 13 '18 at 10:37
@epiphany, There is no problem with your code as I have tested, but it can be simplified. — Aria, May 13 '18 at 12:35
@aria The problem now is the calculation isnt accurate ie between 23/05/2018 & 31/05/2018 it shows 6, it should be 7 days. And it doesnt take the dates into consideration during calculation .Any idea?thanks — epiphany, May 13 '18 at 12:47

Nkosi · Accepted Answer · 2018-05-13T17:23:18.010

5

Keep it simple

public int DaysLeft(DateTime startDate, DateTime endDate, Boolean excludeWeekends, List<DateTime> excludeDates) {
    int count = 0;
    for (DateTime index = startDate; index <= endDate; index = index.AddDays(1)) {
        if (excludeWeekends && (index.DayOfWeek == DayOfWeek.Sunday || index.DayOfWeek == DayOfWeek.Saturday))
            continue;

        if (excludeDates.Contains(index.Date))
            continue;

        count++;
    }
    return count;
}

If the date is a weekend and excludeWeekends flagged, continue on to next date, if date is included in excludeDates continue, else count the day.

edited May 13 '18 at 17:23

answered May 13 '18 at 13:43

Nkosi

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@epiphany which list? – Nkosi May 13 '18 at 13:57
List excludeDates – epiphany May 13 '18 at 13:58
@epiphany you already showed that in the button click. you just add the dates to the list before calling `DaysLeft`. eg: `mylist.Add( DateTime.ParseExact("SomeOtherDateHere", "dd/MM/yyyy", CultureInfo.InvariantCulture));` – Nkosi May 13 '18 at 13:59
if i want to add another date (ie 07/05/2018) to the List, can i do this list.Add(Convert.ToDateTime("07-05-2018")); – epiphany May 13 '18 at 14:02
You should be able to. yes. make sure to validate data formats – Nkosi May 13 '18 at 14:03
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/170955/discussion-between-epiphany-and-nkosi). – epiphany May 13 '18 at 14:07

c# Web app How to get no of working days exclude weekends and public holidays

1 Answers1