Imports System

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Public Module Module1

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    'define number of students.

    'change this in final version

    Const NUM_STUDENTS = 4

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

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    Const MSG_RESULT_INCORRECT = "Results need to be between 20 and 100"

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

    Private IDs(NUM_STUDENTS - 1) as integer

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    Private ENGs(NUM_STUDENTS - 1) as integer

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    Private SCIs(NUM_STUDENTS - 1) as integer

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    Private MATs(NUM_STUDENTS - 1) as integer

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    'trick code beneath - ignore if confused

    '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}

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    Public Sub Main()

        'setup the menu

        Dim anIDS(4) as integer

        Dim nOption as integer

        Do While nOption <> -1

            Console.WriteLine(" Mark  Analysis System. What Do you want to do.Enter 1 to enter marks, 2 to display, 3 to search , -1 to quit")

            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

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            Console.WriteLine(" Mark  Analysis System. What Do you want to do.Enter 1 to enter marks, 2 to display, 3 to search , -1 to quit")

            nOption = Console.ReadLine()

        Loop

    End Sub

​

    Public Sub DisplayData()

        Console.writeline("{0,10}{1,10}{2,10}{3,10}", "ID", "English", "Maths", "Science")

        for i as integer = 0 to IDs.Length-1

            Console.writeline("{0,10}{1,10}{2,10}{3,10}", IDS(i), Engs(i), Mats(i), Scis(i))

        Next

    End sub

​

    Public Sub InputData()

        'get input

        Dim sIn as string ' 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

            Console.writeline(" Enter ID and Results.Format is: ID, EnglishResult, MathResult, ScienceResult ")

            sIn = Console.ReadLine()

            Dim asIn = sIn.Split(",")

            '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)

            isvalid = validate_ID(nTemp)

            Do while isvalid = false

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

                nTemp = Console.readline()

                isvalid = validate_ID(nTemp)

            Loop

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            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)

            'validate the english result

            isvalid = Validate_Results(nTemp)

            do while isvalid = false

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

                nTemp = Console.readline()

                isvalid = validate_Results(nTemp)

            Loop

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            ENGs(i) = nTemp

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

            nTemp = asIN(2)

            'validate the maths result

            isvalid = Validate_Results(nTemp)

            do while isvalid = false

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

                nTemp = Console.readline()

                isvalid = validate_Results(nTemp)

            Loop

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            MATs(i) = nTemp

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

            nTemp = asIN(3)

            'validate the maths result

            'valiate the science result

            isvalid = Validate_Results(nTemp)

            do while isvalid = false

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

                nTemp = Console.readline()

                isvalid = validate_Results(nTemp)

            Loop

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            SCIs(i) = nTemp

        Next

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

        PrintArray(IDs)

        PrintArray(ENGs)

        PrintArray(MATs)

        PrintArray(SCIs)

        'complicated stuff below

        'allarryas is an array of arrays

        'so item is an array

        for each item as integer() in AllArrays

            PrintArray(item)

        Next

    End Sub

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    Function Validate_Results(nResult as integer) as boolean

        'check the value

        if nResult > 100 then

            Console.writeline(MSG_RESULT_INCORRECT)

            return False

        else

            Return True

        end if

    End Function

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    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 10,000 and 99,999. ")

            return false

        end if

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

            Console.WriteLine("ID not unique")

            return false

        end if

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        'if the code gets to here, ID is valid

        Return True

    End Function

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    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

End Module

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