Imports System.Collections.Specialized

Public Class NameValueCollectionEx
    Inherits NameValueCollection

    Private _RecordDelimiter As String = "&"
    Private _FieldDelimiter As String = "="

    Public Property FieldDelimiter() As String
        Get
            Return _FieldDelimiter
        End Get
        Set(ByVal value As String)
            _FieldDelimiter = value
        End Set
    End Property

    Public Property RecordDelimiter() As String
        Get
            Return _RecordDelimiter
        End Get
        Set(ByVal value As String)
            _RecordDelimiter = value
        End Set
    End Property

    Public Property DataString() As String
        Get
            Dim sOut As String = Nothing
            For Each sItem As String In MyBase.AllKeys
                sOut &= sItem & _FieldDelimiter & MyBase.Item(sItem) & _RecordDelimiter
            Next
            sOut = sOut.Substring(0, sOut.Length - 1)
            Return sOut
        End Get
        Set(ByVal value As String)
            Dim sData() As String = Split(value, _RecordDelimiter)
            For Each sItem As String In sData
                MyBase.Add(Split(sItem, _FieldDelimiter)(0), Split(sItem, _FieldDelimiter)(1))
            Next
        End Set
    End Property

    Public Sub New()

    End Sub

    Public Sub New(ByVal NameValueString As String)
        DataString = NameValueString
    End Sub

    Public Sub New(ByVal NameValueString As String, ByVal RecordDelimiter As String, ByVal FieldDelimiter As String)
        _RecordDelimiter = RecordDelimiter
        _FieldDelimiter = FieldDelimiter
        DataString = NameValueString
    End Sub

End Class

Module Module1

    Sub Main()

        Dim InputStr As String = "FirstName=Ben&MiddleName=&LastName=Alabaster&EmpId=259486"
        Dim NVC As New NameValueCollectionEx(InputStr)

        For Each Item As String In NVC.AllKeys
            Console.WriteLine(Item & ": " & NVC(Item))
        Next

        Console.ReadLine()

    End Sub

End Module