NumberFormatInfo recognizes the "pos" as the positive sign and "neg" as the negative sign. : NumberFormatInfo « I18N Internationlization « VB.Net Tutorial

1. VB.Net Tutorial
2. I18N Internationlization
3. NumberFormatInfo

Imports System.Globalization

Module Example
    Public Sub Main()
        Dim provider As New NumberFormatInfo()
        provider.PositiveSign = "pos "
        provider.NegativeSign = "neg "

        Dim values() As String = {"-3", "+3", "pos 3"}

        For Each value As String In values
            Try
                Console.WriteLine("{0,17}", Convert.ToUInt16(value, provider))
            Catch e As FormatException
                Console.WriteLine("{0,17}", e.GetType().Name)
            End Try
        Next
    End Sub
End Module