Bug 4523 - IgnoreCase inline option in Regex doesn't work if option gets turned on and off
Summary: IgnoreCase inline option in Regex doesn't work if option gets turned on and off
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-04-19 11:58 UTC by eb1
Modified: 2014-11-23 23:00 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description eb1 2012-04-19 11:58:24 UTC
using System;
using System.Text.RegularExpressions;

public class X
        public static void Main()
                Console.WriteLine(new Regex("A(?i)b(?-i)C").Match("ABC"));

Expected behavior: the regex matches ABC

Actual behavior: regex doesn't match because (?-i) overrides (?i).
Comment 1 eb1 2012-04-19 11:59:19 UTC
Workaround: Use a subexpression inside of the option instead: new Regex("A(?i:b)C")
Comment 2 Miguel de Icaza [MSFT] 2014-11-23 23:00:13 UTC