例: InStrB function

' The value 5 (the position of the byte where the first
' occurrence of littleStr begins in bigStr) is assigned to
' the variable positionOfByte.
Dim bigStr As String, littleStr As String
Dim positionOfByte As Long
bigStr$ = "abcdefghi"
littleStr$ = "efg"
positionOfByte& = InStrB(1, bigStr$, littleStr$)
Print positionOfByte& ' Output:  5