Binaryworld - Count distinct characters in a string ... [ VB -> String ]

When you need to count how many occurrences of a given character are in a string, you might be tempted to go along the "traditional" Visual Basic way:

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' count spaces
  For i = 1 To Len(text)
    If Mid$(text, i, 1) = " " Then count = count + 1
  Next

Everything is easier if you use the capability to move a string into a Byte array. Here is a complete routine:
' count spaces

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Function CountSpaces(ByVal sText As String) As Long
  Dim bArr() As Byte
  Dim i As Long
  Dim count As Long

  bArr() = sText
  For i = 0 To UBound(bArr) Step 2
    ' if this char is a space, increase the counter
    If bArr(i) = 32 Then count = count + 1
  Next
  CountSpaces = count
End Function

This approach can be up to three times faster than the traditional one.