Function which Removes Only Non-ASCII characters in a column in access table - vba

Question

I have a access table and i am writing a vba code to remove non-ascii characters from the table, i have tried using below two functions
Public Function removeall(stringData As String) As String
Dim letter As Integer
Dim final As String
Dim i As Integer
For i = 1 To Len(stringData) 'loop thru each char in stringData
letter = Asc(Mid(stringData, i, 1)) 'find the char and assign asc value
Select Case letter 'Determine what type of char it is
Case Is < 91 And letter > 64 'is an upper case char
final = final & Chr(letter)
Case Is < 123 And letter > 96 'is an lower case char
final = final & Chr(letter)
Case Is = 32 'is a space
final = final & Chr(letter)
End Select
Next i
removeall = final
End Function
And also tried using below function
Public Function Clean(InString As String) As String
'-- Returns only printable characters from InString
Dim x As Integer
For x = 1 To Len(InString)
If Asc(Mid(InString, x, 1)) > 31 And Asc(Mid(InString, x, 1)) < 127 Then
Clean = Clean & Mid(InString, x, 1)
End If
Next x
End Function
But the problem is : In removeall function it removes everything including # and space characters.. And In Clean function also removes special characters as well.
I need a correct function which retains key board characters and removes all other characters
Examples of strings in tables are :
1) "ATTACHMENT FEEDING TUBE FITS 5-18 ºFR# "
2) "CATHETER FOLEY 3WAY SILI ELAST 20FR 30ML LATEXº"
Any help would be greatly appreciated
Output should be like
1) "ATTACHMENT FEEDING TUBE FITS 5-18 FR"
2) "CATHETER FOLEY 3WAY SILI ELAST 20FR 30ML LATEX"

Answer 1

One approach would be to use a whitelist of accepted characters. e.g.
' You can set up your domain specific list:
Const Whitelist = "1234567890" & _
"qwertyuiopasdfghjklzxcvbnm" & _
"QWERTYUIOPASDFGHJKLZXCVBNM" & _
" `~!##$%^&*()_-=+[]{};:""'|\<>?/ –"
Public Sub test()
Debug.Print Clean("ATTACHMENT FEEDING TUBE FITS 5-18 ºFR#")
Debug.Print Clean("CATHETER FOLEY 3WAY SILI ELAST 20FR 30ML LATEXº")
End Sub
Public Function isAllowed(char As String) As Boolean
isAllowed = InStr(1, Whitelist, char, vbBinaryCompare) > 0
End Function
Public Function Clean(dirty As String) As String
'-- Returns only printable characters from dirty
Dim x As Integer
Dim c As String
For x = 1 To Len(dirty)
c = Mid(dirty, x, 1)
If isAllowed(c) Then
Clean = Clean & c
End If
Next x
End Function

Answer 2

Alternate approach that preserves ALL ASCII characters, without working with a whitelist, in a single function:
Public Function RemoveNonASCII(str As String) As String
Dim i As Integer
For i = 1 To Len(str)
If AscW(Mid(str, i, 1)) < 127 Then 'It's an ASCII character
RemoveNonASCII = RemoveNonASCII & Mid(str, i, 1) 'Append it
End If
Next i
End Function