Option Strict On
Option Explicit On
Public Class frmMain

    Private Sub btnFindSign_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnFindSign.Click
        Dim birthday As Date
        'Check to see if the date in the textbox is valid
        If IsDate(txtBirthDay.Text) Then
            'stores the value fromt the birthday text box into the variable birthday
            birthday = CDate(txtBirthDay.Text)
            'Call getSign and stores the result into the text box
            txtSign.Text = getSign(birthday)
        Else
            'Display Error
            MessageBox.Show("Please Enter a Valid Date", "Invalid Date")
        End If
    End Sub

    'Function Name: getSign
    'Returns:       Zodiac sign as a string
    'Parameters:    inDate of type date
    'Description:   Takes in a date as and returns the corresponding zodiac sign 

    Function getSign(ByVal inDate As Date) As String
        'Gets the day and the month from the incoming date
        Dim inMonth As Integer = Month(inDate)
        Dim inDay As Integer = DateAndTime.Day(inDate)
        Dim sign As String

        Select Case inMonth
            Case 1
                If inDay < 20 Then
                    sign = "Capricorn"
                Else
                    sign = "Aquarius"
                End If
            Case 2
                If inDay < 19 Then
                    sign = "Aquarius"
                Else
                    sign = "Pisces"
                End If
            Case 3
                If inDay < 21 Then
                    sign = "Pisces"
                Else
                    sign = "Aries"
                End If
            Case 4
                If inDay < 20 Then
                    sign = "Aries"
                Else
                    sign = "Taurus"
                End If
            Case 5
                If inDay < 21 Then
                    sign = "Taurus"
                Else
                    sign = "Gemini"
                End If
            Case 6
                If inDay < 21 Then
                    sign = "Gemini"
                Else
                    sign = "Cancer"
                End If
            Case 7
                If inDay < 23 Then
                    sign = "Cancer"
                Else
                    sign = "Leo"
                End If
            Case 8
                If inDay < 23 Then
                    sign = "Leo"
                Else
                    sign = "Virgo"
                End If
            Case 9
                If inDay < 23 Then
                    sign = "Virgo"
                Else
                    sign = "Libra"
                End If
            Case 10
                If inDay < 23 Then
                    sign = "Libra"
                Else
                    sign = "Scorpio"
                End If
            Case 11
                If inDay < 22 Then
                    sign = "Scorpio"
                Else
                    sign = "Sagittarius"
                End If
            Case 12
                If inDay < 22 Then
                    sign = "Sagittarius"
                Else
                    sign = "Capricorn"
                End If
            Case Else
                sign = "Invalid Month"
        End Select

        Return sign
    End Function
End Class