| Character |
Description |
| \ |
Marks the next character as a special character, a literal character, a back-reference, or an octal escape. For example, "n" matches the character "n". "\n" matches a newline character. The sequence "\\" matches "\" and "\( matches "(". |
| ^ |
Matches the beginning position of the input string. If the Multiline property of the RegExp object is set, ^ also matches the position after "\n" or "\r". |
| $ |
Matches the end position of the input string. If the Multiline property of the RegExp object is set, $ also matches the position before "\n" or "\r". |
| * |
Matches the preceding sub-expression zero or more times. For example, zo* can match "z" and "zoo". * is equivalent to {0,}. |
| + |
Matches the preceding sub-expression one or more times. For example, "zo+" can match "zo" and "zoo", but cannot match "z". + is equivalent to {1,}. |
| ? |
Matches the preceding sub-expression zero or one time. For example, "do(es)?" can match "do" or "does". ? is equivalent to {0,1}. |
| {n} |
n is a non-negative integer. Matches exactly n times. For example, "o{2}" cannot match the "o" in "Bob", but can match the two o's in "food". |
| {n,} |
n is a non-negative integer. Matches at least n times. For example, "o{2,}" cannot match the "o" in "Bob", but can match all o's in "foooood". "o{1,}" is equivalent to "o+". "o{0,}" is equivalent to "o*". |
| {n,m} |
m and n are both non-negative integers, where n <= m. Matches at least n times and at most m times. For example, "o{1,3}" will match the first three o's in "fooooood". "o{0,1}" is equivalent to "o?". Note that there cannot be spaces between the comma and the two numbers. |
| ? |
When this character follows any other quantifier (*, +, ?, {n}, {n,}, {n,m}), the matching mode is non-greedy. The non-greedy mode matches as little of the searched string as possible, while the default greedy mode matches as much of the searched string as possible. For the string "oooo", "o+?" will match a single "o", while "o+" will match all "o's". |
| . |
Matches any single character except "\n". To match any character including "\n", use a pattern like "[.\n]". |
| (pattern) |
Matches pattern and captures this match. The captured match can be obtained from the resulting Matches collection, accessed through the SubMatches collection in VBScript or the $0…$9 properties in JScript. To match parentheses characters, use "\( or "\)". |
| (?:pattern) |
Matches pattern but does not capture the match, meaning it is a non-capturing match and is not stored for later use. This is useful when combining parts of a pattern using the or character "("|". For example, "industr(?:y|ies)" is a more concise expression than "industry|industries". |
| (?=pattern) |
Positive lookahead, matches if the string starts with that matches pattern. This is a non-capturing match, meaning it does not need to be captured for later use. For example, "Windows(?=95|98|NT|2000)" can match “Windows” in “Windows2000”, but cannot match "Windows" in "Windows3.1". Lookaheads do not consume characters, which means that after a match occurs, the next search for a match starts immediately after the last match, not from the character that includes the lookahead. |
| (?!pattern) |
Negative lookahead, matches if the string does not start with that matches pattern. This is a non-capturing match, meaning it does not need to be captured for later use. For example, "Windows(?!95|98|NT|2000)" can match “Windows” in “Windows3.1”, but cannot match "Windows" in "Windows2000". Lookaheads do not consume characters, which means that after a match occurs, the next search for a match starts immediately after the last match, not from the character that includes the lookahead. |
| x|y |
Matches x or y. For example, "z|food" can match “z” or “food”. "(z|f)ood" matches “zood” or "food". |
| [xyz] |
Character set. Matches any one of the contained characters. For example, "[abc]" can match the "a" in "plain". |
| [^xyz] |
Negative character set. Matches any character not contained. For example, "[^abc]" can match the "p" in "plain". |
| [a-z] |
Character range. Matches any character within the specified range. For example, "[a-z]" can match any lowercase letter from "a" to "z". |
| [^a-z] |
Negative character range. Matches any character not in the specified range. For example, "[^a-z]" can match any character not in the "a" to "z" range. |
| \b |
Matches a word boundary, referring to the position between a word and a space. For example, "er\b" can match "er" in "never", but cannot match "er" in "verb". |
| \B |
Matches a non-word boundary. "er\B" can match "er" in "verb", but cannot match "er" in "never". |
| \cx |
Matches a control character indicated by x. For example, \cM matches a Control-M or carriage return character. x must be one of A-Z or a-z. Otherwise, c is treated as a literal "c" character. |
| \d |
Matches a digit character. Equivalent to [0-9]. |
| \D |
Matches a non-digit character. Equivalent to [^0-9]. |
| \f |
Matches a form feed character. Equivalent to \x0c and \cL. |
| \n |
Matches a newline character. Equivalent to \x0a and \cJ. |
| \r |
Matches a carriage return character. Equivalent to \x0d and \cM. |
| \s |
Matches any whitespace character including spaces, tabs, form feeds, and so on. Equivalent to [\f\n\r\t\v]. |
| \S |
Matches any non-whitespace character. Equivalent to [^\f\n\r\t\v]. |
| \t |
Matches a tab character. Equivalent to \x09 and \cI. |
| \v |
Matches a vertical tab character. Equivalent to \x0b and \cK. |
| \w |
Matches any word character including underscores. Equivalent to "[A-Za-z0-9_]". |
| \W |
Matches any non-word character. Equivalent to "[^A-Za-z0-9_]". |
| \xn |
Matches n, where n is a hexadecimal escape value. Hexadecimal escape values must be exactly two digits long. For example, "\x41" matches "A". "\x041" is equivalent to "\x04&1". ASCII encoding can be used in regular expressions. |
| \num |
Matches num, where num is a positive integer that refers to a captured match. For example, "(.)\1" matches two consecutive identical characters. |
| \n |
Indicates an octal escape value or a back-reference. If there have been at least n captured sub-expressions before \n, then n is a back-reference. Otherwise, if n is an octal digit (0-7), then n is an octal escape value. |
| \nm |
Indicates an octal escape value or a back-reference. If there have been at least nm captured sub-expressions before \nm, then nm is a back-reference. If there have been at least n captures before \nm, then n is a back-reference followed by literal m. If neither of the previous conditions are met, if n and m are both octal digits (0-7), then \nm matches the octal escape value nm. |
| \nml |
If n is an octal digit (0-3) and m and l are both octal digits (0-7), then matches the octal escape value nml. |
| \un |
Matches n, where n is a Unicode character represented by four hexadecimal digits. For example, \u00A9 matches the copyright symbol (©). |