'**************************************
' Name: ConvertToSoundex
' Description:Converts a name or word st
'     ring to a four digit code following Soun
'     dex rules.
Similar code is used by geniological groups and the US Census Bureau For
looking up names by phonetic sound. For example, the name Darrell can
be spelled many different ways. Regardles of how you spell it, (Daryl, Derrel,
Darel, etc.) the Soundex code is always D640. Therefore, you assign a field
In your database To the Soundex code and Then query the database using
the code, all instances of Darrell regarless of spelling will be returned. Refer
To the code comment section For more information.
' By: Darrell Sparti
'
' Inputs:A single name or word string.
'
' Returns:A four digit alphanumeric Soun
'     dex code.
'
' Side Effects:This code has not been co
'     mmercially tested.
'
'This code is copyrighted and has' limited warranties.Please see http://w
'     ww.Planet-Source-Code.com/vb/scripts/Sho
'     wCode.asp?txtCodeId=1061&lngWId;=1'for details.'**************************************

'***************************************
'     ********************************
'Function Name:ConvertToSoundex
'Argument:A single name or word string
'Return value:A 4 character code based o
'     n Soundex rules
'Author:Darrell Sparti
'EMail:dsparti@allwest.net
'Date: 9-20-98
'Description:All Soundex codes have 4 al
'     phanumeric
' characters, no more and no less, regar
'     dless
' of the length of the string. The first
'     
' character is a letter and the other 3 
'     are
' numbers. The first letter of the strin
'     g is
' the first letter of the Soundex code. 
'     The
' 3 digits are defined sequentially from
'     the
' string using the following key:
' 1 = bpfv
' 2 = cskgjqxz
' 3 = dt
' 4 = l
' 5 = mn
' 6 = r
' No Code = aehiouyw
' If the end of the string is reached be

'     fore
    ' filling in 3 numbers, 0's complete the
    '     code.
    ' Example: Swartz= S632
    ' Example: Darrell= D640
    ' Example: Schultz = S432
    'NOTE:I have noticed some errors in othe
    '     r versions
    'of soundex code. Most noticably is the
    'fact that not only must the code ignore
    '     
    'the second letter in repeating letters
    '(ll,rr,tt,etc. for example), it must al
    '     so
    'ignore letters next to one another with
    '     the
    'same soundex code (s and c for example)
    '     .
    'Other wise, in the example above, Schul
    '     tz
    'would return a value of S243 which is
    'incorrect.
    '***************************************
    '     *****************************
    Option Explicit
Public Function ConvertToSoundex(sInString As String) As String

    Dim sSoundexCode As String
    Dim sCurrentCharacter As String
    Dim sPreviousCharacter As String
    Dim iCharacterCount As Integer
    'Convert the string to upper case letter
    '     s and remove spaces
    sInString = UCase$(Trim(sInString))
    'The soundex code will start with the fi
    '     rst character _
    of the String
    sSoundexCode = Left(sInString, 1)
    'Check the other characters starting at 
    '     the second character
    iCharacterCount = 2
    'Continue the conversion until the sound
    '     ex code is 4 _
    characters Long regarless of the length of the String
    Do While Not Len(sSoundexCode) = 4
        'If the previous character has the same 
        '     soundex code as _
        current character or the previous character is the same _
        as the current character, ignor it and move onto the Next
        sCurrentCharacter = Mid$(sInString, iCharacterCount, 1)
        sPreviousCharacter = Mid$(sInString, iCharacterCount - 1, 1)
        If sCurrentCharacter = sPreviousCharacter Then
            iCharacterCount = iCharacterCount + 1
        ElseIf InStr("BFPV", sCurrentCharacter) Then
            If InStr("BFPV", sPreviousCharacter) Then
                iCharacterCount = iCharacterCount + 1
            End If

        ElseIf InStr("CGJKQSXZ", sCurrentCharacter) Then
            If InStr("CGJKQSXZ", sPreviousCharacter) Then
                iCharacterCount = iCharacterCount + 1
            End If

        ElseIf InStr("DT", sCurrentCharacter) Then
            If InStr("DT", sPreviousCharacter) Then
                iCharacterCount = iCharacterCount + 1
            End If

        ElseIf InStr("MN", sCurrentCharacter) Then
            If InStr("MN", sPreviousCharacter) Then
                iCharacterCount = iCharacterCount + 1
            End If

        Else
        End If

        
        'If the end of the string is reached bef
        '     ore there are 4 _
        characters In the soundex code, add 0 until there are _
        a total of 4 characters In the code
        If iCharacterCount > Len(sInString) Then
            sSoundexCode = sSoundexCode & "0"
            'Otherwise, concatenate a number to the 
            '     soundex code _
            base On soundex rules
        Else
            sCurrentCharacter = Mid$(sInString, iCharacterCount, 1)
            If InStr("BFPV", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "1"
            ElseIf InStr("CGJKQSXZ", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "2"
            ElseIf InStr("DT", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "3"
            ElseIf InStr("L", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "4"
            ElseIf InStr("MN", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "5"
            ElseIf InStr("R", sCurrentCharacter) Then
                sSoundexCode = sSoundexCode & "6"
            Else
            End If

        End If

        
        'Check the next letter
        iCharacterCount = iCharacterCount + 1
    Loop

    'Return the soundex code for the string
    ConvertToSoundex = sSoundexCode
End Function