Regular Expressions =================== Public domain ******************************************************************************** Patterns of characters that are used in searching databases
 Metacharacter Meaning Example Explanation . Exactly one character, not null . One character, not null. * zero or more times (like {0,}) ab*c ac, abc, abbc, abbbc, ... + once or more times (like {1,}) ab+c abc, abbc, abbbc, ... ? zero or once (like {0,1}) ab?c ac,abc. ^ Beginning of the line ^abc Lines witch begin with "abc". \$ End of the line abc\$ Lines witch end with "abc". \ Escape carahcter \. dot character. [] One occurence of list [abc] matches a,b or c. [-] Range of characters [a-d] matches a,b,c or d. [^] Reverse range of characters [^a-d] matches not a,b,c or d. (|) alternative text (abc|def) matches abc or def. \d exactly one digit \d\d 00, 01, ..., 99. \D everything except digit \D\D not 00,...,99. \w exactly one letter,number or underscore (like [A-z0-9_]) \w a, 1, _, .... \W everything except letter, number or underscore(like [^A-z0-9_]) \W @,#,... \s exactly one whitespace (space,tab,newline) \s \S everything except whitespace \S @ \b word boundary \bdef def (not abcdef) \B non-word boundary \Bdef abcdef (not def) \t tab character \n carriage return \nnn octal number \007 bell character {m} character repetitions (m times) a{2} aa {m,n} character repetitions (minimum m, maximum n) a{2,3} aa,aaa {m,} character repetitions (minimum m) a{2,} aa,aaa,aaaa,aaaaa,...
******************************************************************************** _BY: Pejman Moghadam_ _TAG: regex_ _DATE: 2009-04-25 00:16:37_