calculate timespan (days) between 2 dates from timepicker in a class

[Marie-Andree]

Hello,
I am trying to pass 2 variables check in date and check out date from 2 different date time picker on a form. The goal is two calculate the number of day between the 2 dates.

Here is what I have so far:
From the form:

[COLOR=#00008B]Public[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Class[/COLOR][COLOR=#000000] FormReservations

[/COLOR][COLOR=#808080]'Declare the new objects:[/COLOR][COLOR=#000000]

[/COLOR][COLOR=#00008B]Private[/COLOR][COLOR=#000000] TheRegularPriceObject [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] ClassRegularPrice


[/COLOR][COLOR=#00008B]Private[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Sub[/COLOR][COLOR=#000000] ButtonCalculateRate_Click[/COLOR][COLOR=#000000]([/COLOR][COLOR=#000000]sender [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Object[/COLOR][COLOR=#000000],[/COLOR][COLOR=#000000] e [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] EventArgs[/COLOR][COLOR=#000000])[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Handles[/COLOR][COLOR=#000000] ButtonCalculateRate[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]Click

TheRegularPriceObject [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]New[/COLOR][COLOR=#000000] ClassRegularPrice[/COLOR][COLOR=#000000]([/COLOR][COLOR=#000000]DateTimePickerCheckIn[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]Value[/COLOR][COLOR=#000000].[/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]ToString[/COLOR][COLOR=#000000]([/COLOR][COLOR=#800000]"dd/MM/yyyy"[/COLOR][COLOR=#000000]),[/COLOR][COLOR=#000000]DateTimePickerCheckOut[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]Value[/COLOR][COLOR=#000000].[/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]ToString[/COLOR][COLOR=#000000]([/COLOR][COLOR=#800000]"dd/MM/yyyy"[/COLOR][COLOR=#000000]))[/COLOR][COLOR=#000000]




        LabelNumberOfDay[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]Text [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] TheRegularPriceObject[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]CalculateNumberOfDay[/COLOR][COLOR=#000000].[/COLOR][COLOR=#000000]ToString[/COLOR][COLOR=#000000]()[/COLOR][COLOR=#000000]
    [/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]If[/COLOR][COLOR=#000000]


[/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Sub

[COLOR=#222426][FONT=Arial]End Class

[/FONT][/COLOR]

This my class:

[COLOR=#00008B]Public[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Class[/COLOR][COLOR=#000000] ClassRegularPrice



[/COLOR][COLOR=#00008B]Protected[/COLOR][COLOR=#000000] CheckInDateVar [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]String[/COLOR][COLOR=#000000]

[/COLOR][COLOR=#00008B]Protected[/COLOR][COLOR=#000000] CheckOutDateVar [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]String[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]Protected[/COLOR][COLOR=#000000] NumberOfDaySpan [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Integer[/COLOR][COLOR=#000000]

[/COLOR][COLOR=#808080]'Constructor: [/COLOR][COLOR=#000000]

[/COLOR][COLOR=#00008B]Public[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Sub[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]New[/COLOR][COLOR=#000000]([/COLOR][COLOR=#00008B]ByVal[/COLOR][COLOR=#000000] CheckInDateConst [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]String[/COLOR][COLOR=#000000],[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]ByVal[/COLOR][COLOR=#000000] CheckOutDateConst [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]String[/COLOR][COLOR=#000000])[/COLOR][COLOR=#000000]

CheckInDate [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] CheckInDateConst
CheckOutDate [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] CheckOutDateConst
CalculateNumberOfDay[/COLOR][COLOR=#000000]()[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Sub[/COLOR][COLOR=#000000]

[/COLOR][COLOR=#00008B]Property[/COLOR][COLOR=#000000] CheckInDate[/COLOR][COLOR=#000000]()[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000]
    [/COLOR][COLOR=#00008B]Get[/COLOR][COLOR=#000000]
        [/COLOR][COLOR=#00008B]Return[/COLOR][COLOR=#000000] CheckInDateVar
    [/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Get[/COLOR][COLOR=#000000]
    [/COLOR][COLOR=#00008B]Set[/COLOR][COLOR=#000000]([/COLOR][COLOR=#00008B]ByVal[/COLOR][COLOR=#000000] Value [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000])[/COLOR][COLOR=#000000]
        CheckInDateVar [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] Value
    [/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Set[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Property[/COLOR][COLOR=#000000]


[/COLOR][COLOR=#00008B]Property[/COLOR][COLOR=#000000] CheckOutDate[/COLOR][COLOR=#000000]()[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000]
    [/COLOR][COLOR=#00008B]Get[/COLOR][COLOR=#000000]
        [/COLOR][COLOR=#00008B]Return[/COLOR][COLOR=#000000] CheckOutDateVar
    [/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Get[/COLOR][COLOR=#000000]
    [/COLOR][COLOR=#00008B]Set[/COLOR][COLOR=#000000]([/COLOR][COLOR=#00008B]ByVal[/COLOR][COLOR=#000000] Value [/COLOR][COLOR=#00008B]As[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Date[/COLOR][COLOR=#000000])[/COLOR][COLOR=#000000]
        CheckOutDateVar [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] Value
    [/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Set[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Property[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]Sub[/COLOR][COLOR=#000000] 


 [/COLOR][COLOR=#808080]'Methods:[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]Sub[/COLOR][COLOR=#000000] CalculateNumberOfDay[/COLOR][COLOR=#000000]()[/COLOR][COLOR=#000000]

    NumberOfDaySpan [/COLOR][COLOR=#000000]=[/COLOR][COLOR=#000000] [/COLOR][COLOR=#000000]([/COLOR][COLOR=#000000]CheckOutDateVar [/COLOR][COLOR=#000000]-[/COLOR][COLOR=#000000] CheckInDateVar[/COLOR][COLOR=#000000])[/COLOR][COLOR=#000000]
[/COLOR][COLOR=#00008B]End[/COLOR][COLOR=#000000] [/COLOR][COLOR=#00008B]Sub[/COLOR]

It is not returning a value and I'm not sure I converted my date to string also, but this is what I have been told to do. I am not sure from there how the calculation should work since this is a string... Any help would be greatly appreciated.
[/COLOR]

 

[jmcilhinney]

Firstly, you've made your code harder for us to read. In future, please post it as plain text like so:

[xcode=vb]your code here[/xcode]
That will add appropriate syntax highlighting.

Don't convert your Dates to Strings. Strings are for text. Dates are not text. The ONLY reason to convert a Date to a String is for display or serialisation. If you want to perform a calculation then do it on binary Dates, NOT text. To calculate the number days between the dates selected in two DateTimePickers you would do this:

Dim startDate As Date = startDatePicker.Value.Date
Dim endDate As Date = endDatePicker.Value.Date
Dim time As TimeSpan = endDate - startDate
Dim days As Integer = time.Days

The Value property of the DateTimePicker gives you a DateTime (a .NET DateTime and a VB.NET Date are the same thing) and getting the Date property of that gives you another DateTime with the same date portion and the time portion zeroed.

 

[JohnH]

Sub Procedures (Visual Basic)

A Sub procedure is a series of Visual Basic statements enclosed by the Sub and End Sub statements. The Sub procedure performs a task and then returns control to the calling code, but it does not return a value to the calling code.

Function Procedures (Visual Basic)

A Function procedure is a series of Visual Basic statements enclosed by the Function and End Function statements. The Function procedure performs a task and then returns control to the calling code. When it returns control, it also returns a value to the calling code.

 

[Marie-Andree]

Thank you,
I will study what you wrote.