devxlogo

InstrTblRev – The last occurrence of a char in a table

InstrTblRev – The last occurrence of a char in a table

' If INCLUDE is True or is omitted, return the last occurrence of a character ' in a group' or -1 if SOURCE doesn't contain any character among those listed in TABLE.' If INCLUDE is False, return the last occurrence of the character in SOURCE' that does not appear in TABLE.'' string indices are zero-based' START = -1 searches from the end of string' TABLE can be in the form "A-Z"Function InstrTblRev(ByVal Start As Integer, ByVal Source As String, _    ByVal Table As String, Optional ByVal Include As Boolean = True, _    Optional ByVal CaseInsensitive As Boolean = False) As Integer    ' create the regular expression    Dim pattern As String    If Include Then        pattern = "[" & Table & "]"    Else        pattern = "[^" & Table & "]"    End If    ' prepare the correct regex option    Dim options As Text.RegularExpressions.RegexOptions    If CaseInsensitive Then        options = Text.RegularExpressions.RegexOptions.IgnoreCase    End If    ' create the Regex object    Dim re As New Text.RegularExpressions.Regex(pattern, options)    ' adjust arguments for backward search    Source = StrReverse(Source)    If Start >= 0 And Start < Source.Length Then        Start = Source.Length - Start    Else        Start = 0    End If    ' find the match    Dim ma As Text.RegularExpressions.Match = re.Match(Source, Start)    ' return the found index, or -1    If ma.Success Then        Return Source.Length - ma.Index - 1    Else        Return -1    End IfEnd Function

devxblackblue

About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

About Our Journalist