Count Letters In a String

[Merri]

InStrB method, just for counting one letter, is much faster than Split or Replace.

Public Function CountLetters(ByRef Text As String, ByRef Letter As String) As Long
    Dim lngA As Long, strL As String * 1
    strL = Letter
    strL = LCase$(strL)
    lngA = InStrB(Text, strL)
    Do While lngA > 0
        CountLetters = CountLetters + (lngA And 1)
        lngA = InStrB(lngA + 1, Text, strL)
    Loop
    strL = UCase$(strL)
    lngA = InStrB(Text, strL)
    Do While lngA > 0
        CountLetters = CountLetters + (lngA And 1)
        lngA = InStrB(lngA + 1, Text, strL)
    Loop
End Function

InStrB is faster than InStr, but requires extra tricks. In this case, (lngA And 1) to ensure we found a start of character.