I'm trying to test a string for alpha chars, if alpha char append char to a
new string
The following does not work. Is there a tweak I can apply?

l_Alpha_chars = "abcd1"
For q = 1 To Len(l_Alpha_chars)
l_chr = Mid(l_Alpha_chars, q, 1)
If l_chr = [a..z] Then
NewStr = NewStr & l_chr
End If
Next q