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  • Metacharacters Defined

    MChar Definition
    ^ Start of a string.
    $ End of a string.
    . Any character (except \n newline)
    | Alternation.
    {...} Explicit quantifier notation.
    [...] Explicit set of characters to match.
    (...) Logical grouping of part of an expression.
    * 0 or more of previous expression.
    + 1 or more of previous expression.
    ? 0 or 1 of previous expression; also forces minimal matching when an expression might match several strings within a search string.
    \ Preceding one of the above, it makes it a literal instead of a special character. Preceding a special matching character, see below.

    Metacharacter Examples

    Pattern Sample Matches
    ^abc abc, abcdefg, abc123, ...
    abc$ abc, endsinabc, 123abc, ...
    a.c abc, aac, acc, adc, aec, ...
    bill|ted ted, bill
    ab{2}c abbc
    a[bB]c abc, aBc
    (abc){2} abcabc
    ab*c ac, abc, abbc, abbbc, ...
    ab+c abc, abbc, abbbc, ...
    ab?c ac, abc
    a\sc a c

    Character Escapes http://tinyurl.com/5wm3wl

    Escaped Char Description
    ordinary characters Characters other than . $ ^ { [ ( | ) ] } * + ? \ match themselves.
    \a Matches a bell (alarm) \u0007.
    \b Matches a backspace \u0008 if in a []; otherwise matches a word boundary (between \w and \W characters).
    \t Matches a tab \u0009.
    \r Matches a carriage return \u000D.
    \v Matches a vertical tab \u000B.
    \f Matches a form feed \u000C.
    \n Matches a new line \u000A.
    \e Matches an escape \u001B.
    \040 Matches an ASCII character as octal (up to three digits); numbers with no leading zero are backreferences if they have only one digit or if they correspond to a capturing group number. (For more information, see Backreferences.) For example, the character \040 represents a space.
    \x20 Matches an ASCII character using hexadecimal representation (exactly two digits).
    \cC Matches an ASCII control character; for example \cC is control-C.
    \u0020 Matches a Unicode character using a hexadecimal representation (exactly four digits).
    \* When followed by a character that is not recognized as an escaped character, matches that character. For example, \* is the same as \x2A.

    Character Classes http://tinyurl.com/5ck4ll

    Char Class Description
    . Matches any character except \n. If modified by the Singleline option, a period character matches any character. For more information, see Regular Expression Options.
    [aeiou] Matches any single character included in the specified set of characters.
    [^aeiou] Matches any single character not in the specified set of characters.
    [0-9a-fA-F] Use of a hyphen (–) allows specification of contiguous character ranges.
    \p{name} Matches any character in the named character class specified by {name}. Supported names are Unicode groups and block ranges. For example, Ll, Nd, Z, IsGreek, IsBoxDrawing.
    \P{name} Matches text not included in groups and block ranges specified in {name}.
    \w Matches any word character. Equivalent to the Unicode character categories [\p{Ll}\p{Lu}\p{Lt}\p{Lo}\p{Nd}\p{Pc}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \w is equivalent to [a-zA-Z_0-9].
    \W Matches any nonword character. Equivalent to the Unicode categories [^\p{Ll}\p{Lu}\p{Lt}\p{Lo}\p{Nd}\p{Pc}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \W is equivalent to [^a-zA-Z_0-9].
    \s Matches any white-space character. Equivalent to the Unicode character categories [\f\n\r\t\v\x85\p{Z}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \s is equivalent to [ \f\n\r\t\v].
    \S Matches any non-white-space character. Equivalent to the Unicode character categories [^\f\n\r\t\v\x85\p{Z}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \S is equivalent to [^ \f\n\r\t\v].
    \d Matches any decimal digit. Equivalent to \p{Nd} for Unicode and [0-9] for non-Unicode, ECMAScript behavior.
    \D Matches any nondigit. Equivalent to \P{Nd} for Unicode and [^0-9] for non-Unicode, ECMAScript behavior.

     

    And now to test.... https://www.regextester.com






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