Condition Operators (If and Else statement)

Question

User119289251 posted

Hi all, I’m learning VB trying to develop a very simple holiday system.

I am working with 2 calendars, so that u can select a start date and end date for a holiday year. But the holiday year starts in December and ends in November of the next year. I wrote a code for it so that when a person selects a start date, and chooses an end date in December, it stops them from adding it with a message, but it’s not giving me what I want.

This is it,

 

If Not Year(CalendarStart.SelectedDate) = Year(CalendarEnd.SelectedDate) Or _

        (Not (Year(CalendarEnd.SelectedDate) = Year(CalendarStart.SelectedDate) - 1 And Month(CalendarEnd.SelectedDate) = 12)) Then

            MessageLabel.Text = "Holiday Year ends in November"

            Exit Sub

        End If

 

At present, it is stopping me from adding any holiday, PLEASE what is wrong with the statement?

 

Answer 1

User-1567259439 posted

Try like this:

If Year(CalendarStart.SelectedDate) <> Year(CalendarEnd.SelectedDate)

If it is still not working, try to output your conditions.  Like This:

If Year(CalendarStart.SelectedDate) <> Year(CalendarEnd.SelectedDate)

   MessageLabel.Text = "CalendarStart=" + Year(CalendarStart.SelectedDate)

Else

   MessageLabel.Text = "CalendarEnd=" + Year(CalendarEnd.SelectedDate)

End If

Answer 2

User119289251 posted

@Illinoistin  Just tried it, it didnt work 

Answer 3

User-1567259439 posted

What was the output of the textbox?  You need to have valid variables to compare.

Answer 4

User-1840559507 posted

If

(Year(CalendarStart.SelectedDate) < Year(CalendarEnd.SelectedDate))

And

Month(CalendarEnd.SelectedDate) = 12 Then

            MessageLabel.Text = "Holiday Year ends in November"

            Exit Sub

        End If

Answer 5

User-952121411 posted

There are (2) conditions you need to check:  is someone picking 'December' from the next year or is someone picking December in the current year and it is not yet December.  Try the code below:

        'The 'AndAlso' operator will not test the second condition if the 1st one does not evalute to 'True'
        'The condition in the 'OR' also makes sure that someone in the current year is not slecting a date in December, and it is not yet December
        If (Year(CalendarEnd.SelectedDate) > Year(CalendarStart.SelectedDate)) AndAlso (Month(CalendarEnd.SelectedDate) = 12) _
            Or ((Month(Now) < 12) AndAlso (Month(CalendarEnd.SelectedDate) = 12)) Then

            MessageLabel.Text = "Holiday Year ends in November"
            Exit Sub

        End If

 

Hope this helps!

Answer 6

User119289251 posted

Thanks so much atconway, it works, but there is now a small problem.

It allows me select December as a Start date and any other month for the end date. But when the start and end date are both in December, it doesnt work.

 

Looking 4ward to ur reply

 

Answer 7

User-952121411 posted

Give the following code a try; I believe it covers every combintation and the results should be as expected:

        If (Year(CalendarEnd.SelectedDate) > Year(CalendarStart.SelectedDate)) AndAlso ((Month(CalendarEnd.SelectedDate) = 12)) _
            Or ((Month(CalendarStart.SelectedDate) <= 11) And (Year(CalendarEnd.SelectedDate) <> Year(CalendarStart.SelectedDate))) _
            Or ((Month(Now) < 12 And (Month(CalendarStart.SelectedDate) <> 12)) AndAlso (Month(CalendarEnd.SelectedDate) = 12)) Then

            MessageLabel.Text = "Holiday Year ends in November"
            Exit Sub

        End If

 

 

Answer 8

User119289251 posted

Thank u so so much, it works