Public Class Form1

    Dim keys(100) As Integer
    Dim movies(100) As String
    Dim numMovies As Integer


    Private Function ExtractLine(ByVal text As String, ByRef line As String, ByRef startPos As Integer, ByRef foundPos As Integer) As Boolean
        ' find the next occurrence of the new line char
        foundPos = text.IndexOf(ControlChars.NewLine, startPos)
        ' check if it was found
        If foundPos = -1 Then
            Return False
        Else
            ' pull out the current line of the file
            line = text.Substring(startPos, foundPos - startPos)
            ' update the starting point for search
            startPos = foundPos + 2
            Return True
        End If
    End Function


    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim allText As String
        Dim lineExists As Boolean
        Dim currentDVD As String
        Dim start As Integer = 0
        Dim foundPos As Integer

        ' check if file exists
        If My.Computer.FileSystem.FileExists("info.txt") Then

            ' read the file contents
            allText = My.Computer.FileSystem.ReadAllText("info.txt")

            ' while not at end, extract line
            Do
                lineExists = ExtractLine(allText, currentDVD, start, foundPos)
                If lineExists Then
                    ' stick the line in the rich text box box
                    rtbCheatersList.AppendText(currentDVD & ControlChars.NewLine)

                    Dim movie As String
                    Dim keyStr As String
                    Dim key As Integer
                    Dim commaPos As Integer
                    commaPos = currentDVD.IndexOf(",")
                    keyStr = currentDVD.Substring(0, commaPos) 
                    movie = currentDVD.Substring(commaPos + 1) 

                    Dim isConverted As Boolean
                    isConverted = Integer.TryParse(keyStr, key)
                    If isConverted Then
                        keys(numMovies) = key
                        movies(numMovies) = movie
                        'MsgBox("movie read in - movie: " & movies(numMovies) _
                        '   & " key: " & keys(numMovies))
                        numMovies = numMovies + 1
                    End If
                End If
            Loop While lineExists
            'Array.Sort(keys)
            'Array.Sort(movies)
        Else
            MsgBox("Please put the info.txt file in the bin folder for the project")
        End If
    End Sub

    Private Sub btnLookUp_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLookUp.Click
        Dim key As Integer
        Dim keyStr As String
        Dim isconverted As Boolean
        Dim found As Boolean = False
        isconverted = Integer.TryParse(txtToFind.Text, key)
        If isconverted Then
            Dim cnt As Integer
            For cnt = 0 To numMovies - 1
                If key = keys(cnt) Then
                    found = True
                    txtFound.Text = movies(cnt)
                End If

            Next cnt
            If Not found Then
                MsgBox("that movie is not found")
            End If
        Else
            MsgBox("please enter a whole number to search for")
        End If
    End Sub
End Class