irc

C#

static void Main(string[] args){

 Regex r = new Regex(@"^(?::(?:([^\s!@]+)(?:(?:!([^\s!@]+))?@([^\s!@]+))?)\s)?([^\s:]+)(?:\s(.*))?$");

 string s = ":nickname!-user@h.o.st PRIVMSG #キクチ系:*.jp :萠え〜";

 GroupCollection gc = r.Match(s).Groups;

 for(int i = 0; i < gc.Count; i++)

  Console.WriteLine(string.Format("[{0}]{1}", i, gc[i]));

}

出力…

[0]:nickname!-user@h.o.st PRIVMSG #キクチ系:*.jp :萠え〜

[1]nickname

[2]-user

[3]h.o.st

[4]PRIVMSG

[5]#キクチ系:*.jp :萠え〜

…完璧♪