{"id":345,"date":"2009-12-06T14:36:19","date_gmt":"2009-12-06T12:36:19","guid":{"rendered":"http:\/\/www.limilabs.com\/blog\/?p=345"},"modified":"2016-09-08T23:01:03","modified_gmt":"2016-09-08T21:01:03","slug":"regex-bug-on-mono","status":"publish","type":"post","link":"https:\/\/www.limilabs.com\/blog\/regex-bug-on-mono","title":{"rendered":"Regex bug on Mono"},"content":{"rendered":"

\"mono\"This is a good advice for all creating applications using .NET that need to work on both Microsoft .NET and Mono.<\/p>\n

It seems that Mono ignores group indexes specified explicitly.
\nHere’s the code to reproduce this problem. <\/p>\n

The results on Mono are incorrect.<\/p>\n

\r\nRegex parser = new Regex("(?<2>.*?),(?<1>.*?),");\r\nMatch match = parser.Match("first,second,");\r\nConsole.WriteLine("Groups[1].Value={0}", match.Groups[1].Value);\r\nConsole.WriteLine("Groups[2].Value={0}", match.Groups[2].Value);\r\n<\/pre>\n
MS implementation:<\/p>\n
\r\nC:\\1\\ConsoleApplication\\1\\bin\\Debug>ConsoleApplication1.exe\r\nGroups[1].Value=second\r\nGroups[2].Value=first\r\n<\/pre>\n
Mono 2.4.2.3 implementation:<\/p>\n
\r\nC:\\1\\ConsoleApplication\\1\\bin\\Debug>mono.exe ConsoleApplication1.exe\r\nGroups[1].Value=first\r\nGroups[2].Value=second\r\n<\/pre>\n
The workaround is simple use names instead of numbers:<\/p>\n
\r\nRegex parser = new Regex("(?<first>.*?),(?<second>.*?),");\r\nMatch match = parser.Match("first,second,");\r\nConsole.WriteLine("Groups[first].Value={0}", match.Groups["first"].Value);\r\nConsole.WriteLine("Groups[second].Value={0}", match.Groups["second"].Value);\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"
This is a good advice for all creating applications using .NET that need to work on both Microsoft .NET and Mono. It seems that Mono ignores group indexes specified explicitly. Here’s the code to reproduce this problem. The results on Mono are incorrect. Regex parser = new Regex("(?<2>.*?),(?<1>.*?),"); Match match = parser.Match("first,second,"); Console.WriteLine("Groups[1].Value={0}", match.Groups[1].Value); Console.WriteLine("Groups[2].Value={0}", […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[35],"class_list":["post-345","post","type-post","status-publish","format-standard","hentry","category-programming","tag-mono"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/posts\/345"}],"collection":[{"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/comments?post=345"}],"version-history":[{"count":3,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/posts\/345\/revisions"}],"predecessor-version":[{"id":5042,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/posts\/345\/revisions\/5042"}],"wp:attachment":[{"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/media?parent=345"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/categories?post=345"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.limilabs.com\/blog\/wp-json\/wp\/v2\/tags?post=345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}