Imports System

Public Module Module1

    Public Function GetNthIndexStringFunc(s As String, t As String, n As Integer) As Integer

        Dim newFound As Integer = -1

        For i As Integer = 1 To n

            newFound = s.IndexOf(t, newFound + 1) 

            If newFound = -1 Then

                Return newFound

            End If

        Next

        Return newFound + 1

    End Function    

​

    Public Sub Main()

        Dim SearchString As String = "!!2!3!4!!!7!8!!"

​

        ' Search for "AND".

        Dim SearchChar As String = "!"

        Dim TestPos As Integer

​

        TestPos = GetNthIndexStringFunc(SearchString, SearchChar, 9)

        Console.WriteLine("9nd Occurrence is at " & TestPos)

    Console.WriteLine("String final: " & Microsoft.VisualBasic.strings.Mid(SearchString, 1, TestPos))

        'if TestPos > 0 Then

        '   TestPos = Microsoft.VisualBasic.strings.InStr(TestPos, SearchString, SearchChar)

        'End if

        'Console.WriteLine("2nd Occurrence is at " & TestPos)

    End Sub

End Module