Imports System

​

Public Module Module1

​

    'define number of students.

    'change this in final version

    Const NUM_STUDENTS = 2

​

    Const MSG_ID_INCORRECT = "ID has incorrect format. ID must be unique and must be between 10,000 and 99,999 inclusive"

​

    Const MSG_RESULT_INCORRECT = "Result is incorrect. Result must be between 20 and 100"

​

    'initialize arrays, use the key Private , when declaring outside a function/subroutine.

    Private IDs(NUM_STUDENTS - 1) as integer

​

    Private ENGs(NUM_STUDENTS - 1) as integer

​

    Private SCIs(NUM_STUDENTS - 1) as integer

​

    Private MATs(NUM_STUDENTS - 1) as integer

​

    'AllArrays is an array of arrays. it lets you do stuff with all the arrays with less code using loops  

    'AllArrays(0) is the arrays IDs, &C

    Private AllArrays()() as integer = {IDS, ENGs, MATs, SCIs}

​

    Public Sub Main()

        'setup the menu

        Dim nOption as integer

        Console.WriteLine(" Thi is the Mark Analysis System. Choose the option to do: Enter 1 to enter marks, 2 to display, 3 to search ")

        nOption = Console.ReadLine()

        Select case nOption

            Case 1

                'input data

                InputData()

            Case 2

                'display data

                DisplayData()

            Case 3

            'search

            Case 4

        'edit (for later)

        End Select

    End Sub

​

    Public Sub InputData() ' subroutine to enter data- as option 1 is selected

        'get input

        Dim sIn as string ' variable to hold input

        Dim IsValid as boolean 'used to flag whether input is valid

        Dim nTemp as integer 'temp value used to hold data before adding it into an array

        For i = 0 to NUM_STUDENTS - 1 'minus 1 so that the index is corrected to match from the number entered

            Console.writeline(" Enter ID & Results in CSV format: ID, EnglishResult, MathResult, ScienceResult ")

            sIn = Console.ReadLine() 'variable name for string of group of student data input

            'we split the input, as the input is 1 string, we want the data to be items in an array so they are easy to access.

            Dim asIn = sIn.Split(", ") 'asIn is name of array with info split into array of string and the IDs and results are integers

            'asIN will be an array of string, and the IDS and results are integers

            'however, VB.Net will implicitly convert into the correct datatype.

            'if you enter a result that is not a number by mistake e.g., 20300,e4,90,80, the code, as written will crash.

            'check the ID first - it is  always the first item in the array asIN

            ntemp = asIn(0) 'validate

            isvalid = Validate_ID(nTemp) ' validate the ID, if not valid keep validating until it is valid

            Do while isvalid = false

                Console.WriteLine("Please re-enter ID")

                nTemp = Console.readline()

                isvalid = Validate_ID(nTemp)

            Loop

​

            IDs(i) = nTemp

            'validate IDs with a while loop

            'check range

            'start with isvalid = true, then change to false if fails validation

            'the English result is  always the first item in the array asIN

            nTemp = asIN(1) ' 1 is the second index position for english result

            isvalid = Validate_Results(nTemp) 'validate the english result

            do while isvalid = false

                Console.WriteLine("Please re-enter Result for English.")

                nTemp = Console.readline()

                isvalid = Validate_Results(nTemp)

            Loop

​

            ENGs(i) = nTemp

            'the Maths result is  always the first item in the array asIN

            nTemp = asIN(2) '2 is the third index position for math

            'validate the maths result

            isvalid = Validate_Results(nTemp)

            do While isvalid = false

                Console.WriteLine("Please re-enter Result for Math.")

                nTemp = Console.readline()

                isvalid = Validate_Results(nTemp)

            Loop

​

            MATs(i) = nTemp

            'the Science result is  always the first item in the array asIN

            nTemp = asIN(3) '3 is the forth index position for science

            ' validate the science result

            isvalid = Validate_Results(nTemp)

            do While isvalid = false

                Console.WriteLine("Please re-enter Result for Science.")

                nTemp = Console.readline()

                isvalid = validate_Results(nTemp)

            Loop

​

            SCIs(i) = nTemp

        Next

​

        Main()

        'print arrays out - just to test code works , remove from final version

        PrintArray(IDs)

        PrintArray(ENGs)

        PrintArray(MATs)

        PrintArray(SCIs)

    'allarrays is an array of arrays

    'so item ia an array

    End Sub

​

    Function Validate_Results(nResult as integer) as boolean

        'check the value

        if nResult < 20 OR nResult > 100 then

            Console.writeline(MSG_RESULT_INCORRECT)

            return False

        else

            Return True

        end if

    End Function

​

    Function Validate_ID(nID as integer) as boolean

        'check the range

        if nID < 9999 OR nID > 99999 then

            Console.WriteLine("ID value incorrect. ID needs to be between 9,999 and 99,999. ")

            return false

        end if

​

        if array.IndexOf(IDs, nID) <> -1 then

            Console.WriteLine("ID not unique")

            return false

        end if

​

        'if the code gets to here, ID is valid

        Return True

    End Function

​

    Public Sub DisplayData() ' subroutine to display data- as option 2 is selected

        'create column for each category

        Dim Category() as string = {"ID", "English", "Math", "Science"}

    Console.WriteLine("{0,-20}{1,-20}{2,-20}{3,-20}", Category(0), Category(1),Category(2),Category(3))

    Console.WriteLine("________________________________________________________________________________")

​

        Console.WriteLine() ' data formatted to be in columns

        for i as integer = 0 to NUM_STUDENTS - 1

            Console.WriteLine("{0,-20}{1,-20}{2,-20}{3,-20}", IDs(i), ENGs(i), MATs(i), SCIs(i))

        Next

​

        Main()

    End Sub

​

    Public Sub PrintArray(the_array as object)

        'this is a subroutine that should print any array regardless of datatype

        For each s as object in the_array

            Console.write("{0} ", s.ToString())

        Next

    End Sub

​

    Public function IsValidate_s(a as string) as boolean

        if a.length > 6 or a.length < 2 then

            console.WriteLine("input needs to be between 2 and 6 chars long")

            Return False

        end if

​

        Return True

    End Function

End Module

​