Find Last Occurance of Substring within a String

Find the starting position of the last occurance of a substring within a string. (With strings, the first character is at position 1)

Dim s As String

s = "Chilkat Software chilkat software"

' The following 4 lines are case-sensitive
Print InStrRev(s, "Software")   ' Prints 9
Print InStrRev(s, "Chilkat")    ' Prints 1
Print InStrRev(s, "xyz")        ' Not found, Prints 0
Print InStrRev(s, "software")   ' Prints 26

' The following 3 lines are case-insensitive
' The 3rd argument is the starting position from the end of the string.
' This should be set to -1 to search the entire string from the end to beginning.
Print InStrRev(s, "software", -1, vbTextCompare)   ' Prints 26
Print InStrRev(s, "chilkat", -1, vbTextCompare)    ' Prints 18
Print InStrRev(s, "xyz", -1, vbTextCompare)        ' Not found, Prints 0