Imports System

Imports System.Collections.Generic

Imports System.Linq

​

Public Module Module1

    Public Sub Main()

        Console.WriteLine(GetCell(0, 0))

    End Sub

    Private Function GetMap(path As String) As IEnumerable(Of IEnumerable(Of String))

        Dim map = New List(Of IEnumerable(Of String))()

        'Dim lines = IO.File.ReadAllLines(path) ' removing because this is a fiddle

        Dim lines = {"1,2,3,4", "5678", "9012", "3456"}

        For Each line In lines

            Dim row = New List(Of String)()

            Dim values = line.Split(","c)

            row.AddRange(values)

            map.Add(row)

        Next

​

        Return map

    End Function

​

    Private _map As IEnumerable(Of IEnumerable(Of String))

    Private Sub LoadMap()

        _map = GetMap("C:/path-to-map")

    End Sub

​

    Private Function GetCell(row As Integer, column As Integer) As String

        If (_map Is Nothing) Then

            LoadMap()

        End If

​

        Return _map.ElementAt(row).ElementAt(column)

    End Function

End Module