select case to check range of a decimal number

Question

i need to check whether a demical is 0 through 49.99 or 50 through 99.99 or 100 through 199.99 or greater than 200. i am trying to do this with select case, but i am not sur

Answer 1

I have my doubts that you've framed this question to say exactly what you mean. Do you really want the first group to encompass just 0 through 49.99? Or do you really mean 0 up to but not including 50, and you simply expect your input to have 2 decimal places or fewer? If you want to group numbers by fifties, say, then it is very strange to write:

Select Case value
    Case Is <= 49.99
        Debug.WriteLine("49.99 or less")
    Case Is <= 99.99
        Debug.WriteLine("greater than 49.99, 99.99 or less")
    ' ... and so on '
End Select

The number 49.995 here falls into the second group, which seems counterintuitive. Picking two decimal places as the cut-off point is arbitrary.

The '<=' operator is not the way to go here; use the '<' operator; it makes a lot more sense:

Select Case value
    Case Is < 50
        Debug.WriteLine("less than fifty")
    Case Is < 100
        Debug.WriteLine("fifty or greater, less than 100")
    ' ... and so on '
End Select

Answer 2

Structure employee
    Dim percent As Decimal
    Dim dayname As DayOfWeek
End Structure

Dim emp As employee

 emp.percent = CDec(45.5)
 emp.dayname = DayOfWeek.Friday

Select Case True

    Case (emp.percent >= 0 And emp.percent <= 49.99 
                   And emp.dayname = Now.DayOfWeek)

        MsgBox("Employee percentage   " & emp.percent 
                & "Name of the day  " & Now.DayOfWeek.ToString)

End Select

Answer 3

I came across this question but these responses still allow too many things to fall in the gaps.

'In this example, a value of 49.991 - 49.999* will fall in the 99.99 category, where I expect it is intended for the 49.99 category
Select Case value
    Case Is <= 49.99
        Debug.WriteLine("first group")
    Case Is <= 99.99
        Debug.WriteLine("second group")
    Case Is <= 199.99
        Debug.WriteLine("third group")
    Case Else
        Debug.WriteLine("fourth group")
End Select

Instead it is better to reverse the order, to avoid having to specify superfluous decimal places in an effort to close the gaps.

Select Case value
    Case Is >= 200
        Debug.WriteLine("fourth group")
    Case Is >= 100
        Debug.WriteLine("third group")
    Case Is >= 50
        '49.9999* will always fall in this group irrespective of number of decimal places
        Debug.WriteLine("second group")
    Case Else
        Debug.WriteLine("first group")
End Select

The Select Case statement only follows only the first true case so even though subsequent cases may also be true, they will be bypassed if caught by an earlier case.

Answer 4

    Select Case aa
        Case 1 To 1.49
            MsgBox(1)
        Case 1.5 To 2
            MsgBox(2)
        Case Else
            MsgBox("was lower than 1 or higher than 2 or between 1.49 and 1.5")
    End Select

this(below) would go into case else

   Dim aa As Double = 1.499

this(below) will go into case 1 to 1.49

   Dim aa As Double = 1.4

this(below) will go into case 1.5 to 2

   Dim aa As Double = 1.78

other way of doing it: From here

    Select Case value
        Case Is <= 49.99
            Debug.WriteLine("first group")
        Case Is <= 99.99
            Debug.WriteLine("second group")
        Case Is <= 199.99
            Debug.WriteLine("third group")
        Case Else
            Debug.WriteLine("fourth group")
    End Select

and maybe this too:

    Select Case true
        Case (value >= 0 andalso value <= 49.99)
            Debug.WriteLine("first group")
        Case (value >= 50 andalso value <= 99.99)
            Debug.WriteLine("second group")
        Case (value >= 100 andalso value <= 199.99)
            Debug.WriteLine("third group")
        Case Else
            Debug.WriteLine("fourth group")
    End Select

Answer 5

AlbertEin is onto something, but to do integer division like that in VB.Net you have to write it like this:

Dim range as Integer
range = someInteger \ 50

Notice the backwards division symbol. From there you can Select Case range.

But really, jvanderh's answer most expresses what you want to do, because it allows for easy addition of cases in the future that don't break on a multiple of 50 and don't require future maintainers to follow the math or know about the \ operator.

Answer 6

This is how I would do it, I use the # to explicitly state the values are of type "double".

   Dim input As Double = 2.99

    Select Case input
        Case 0.0# To 49.99#
            Response.Write("Between 0 to 49.99")
        Case 50.0# To 99.99#
            Response.Write("Between 50 and 99.99")
        Case Else
            Response.Write("The value did not fall into a range.")
    End Select