.net - How to use C# regular expressions to emulate forum tags -

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i building forum , want able use simple square bracket tags allow users format text. accomplishing parsing string , looking tags. it's tedious, when run tag [url=http://www.something.com]some text[/url]. having parse attribute, , value, , make sure has proper opening , closing tags kind of pain , seems silly. know how powerful regular expressions i'm not @ them , frustrate me no end.

any of regex gurus willing me out? think example me started. regex finding tags [b]bolded text[/b] , tags attributes link 1 listed above helpful. in advance!

edit: links laymen's terms tutorials regex helpful.

this should work. "=something.com" optional , accommodates single or double quotes , makes sure closing tag matches opening tag. 

    protected void page_load(object sender, eventargs e)     {         string input = @"my link: [url='http://www.something.com'][b]some text[/b][/url] awesome. jazz hands activate!!";         string result = parse(input);     }  //result: link: <a href="http://www.something.com"><b>some text</b></a> awesome. jazz hands activate!!       private static string parse(string input)     {         string regex = @"\[([^=]+)[=\x22']*(\s*?)['\x22]*\](.+?)\[/(\1)\]";         matchcollection matches = new regex(regex).matches(input);         (int = 0; < matches.count; i++)         {             var tag = matches[i].groups[1].value;             var optionalvalue = matches[i].groups[2].value;             var content = matches[i].groups[3].value;              if (regex.ismatch(content, regex))              {                 content = parse(content);             }              content = handletags(content, optionalvalue, tag);              input = input.replace(matches[i].groups[0].value, content);         }          return input;     }      private static string handletags(string content, string optionalvalue, string tag)     {         switch (tag.tolower())         {             case "url":                 return string.format("<a href=\"{0}\">{1}</a>", optionalvalue, content);             case "b":                 return string.format("<b>{0}</b>", content);             default:                 return string.empty;         }     }

update

now i'm having fun this. cleaned bit , replaced " \x22 entire string can escaped per @brad christie's suggestion. regex won't break if there "[" or "]" characters in content. handles tags recursively


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