Regular expression quick start guide
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| − | ! | + | ! width="250" align="left" | Regular Expression Pattern |
! align="left" | Explanations | ! align="left" | Explanations | ||
! align="left" | Examples<br> | ! align="left" | Examples<br> | ||
|- | |- | ||
| − | | | + | | Meta characters [\^$.|?*+(<br> |
| | | | ||
| − | Special caracters used in regex. | + | Special caracters used in regex. |
*Must be escape with backslash "\" to use a literal characters. | *Must be escape with backslash "\" to use a literal characters. | ||
| − | | | + | | <br> |
|- | |- | ||
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| − | Literal characters<br> | + | Literal characters<br> |
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| − | All characters (except the metacharacters) match a single instance of themselves. <br> | + | All characters (except the metacharacters) match a single instance of themselves. <br> |
*{ and } are literal characters, unless they're part of a valid regular expression token (e.g. the {n} quantifier). | *{ and } are literal characters, unless they're part of a valid regular expression token (e.g. the {n} quantifier). | ||
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| ''/a/'' matches "a"<br> | | ''/a/'' matches "a"<br> | ||
|- | |- | ||
| − | | <br> | + | | [characters]<br> |
| − | | <br> | + | | Character classes or character set. A character class matches a single character out of all the possibilities offered by the character class.<br> |
| − | | <br> | + | | ''/[0-9]/'' matches a single digit<br> |
| + | |- | ||
| + | | [\d]<br> | ||
| + | | Shorthand character classes matching digits. Same as [0-9].<br> | ||
| + | | ''/[\d]/'' matches a single digit<br> | ||
| + | |- | ||
| + | | .<br> | ||
| + | | Dot matches any characters.<br> | ||
| + | | ''/a.c/'' matches both "a4c" and "ayc"'''<br>''' | ||
|- | |- | ||
| ^ | | ^ | ||
| − | | Matches | + | | Matches at the start of the string the regex pattern is applied to. Matches a position rather than a character. |
| <br> | | <br> | ||
|- | |- | ||
| $ | | $ | ||
| − | | Matches the end of a | + | | Matches at the end of the string the regex pattern is applied to. Matches a position rather than a character. |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | {m,n}<br> |
| − | | Matches | + | | Matches at least “m” and at most “n” occurrences of preceeding character, character class or group.<br> |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | * |
| − | | Matches | + | | Matches '''zero '''or '''more '''occurrences of preceeding character, character class or group. |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | + |
| − | | | + | | Matches '''one '''or '''more '''occurrences of preceeding character, character class or group.'''<br>''' |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | ? |
| − | | Matches zero or | + | | Matches '''zero '''or '''one '''occurrences of preceeding character, character class or group. |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | () |
| − | | | + | | Parentheses are used for group or capturing group<br> |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | \0, \1, \2, ... |
| − | | | + | | Substitute the value matched by the nth grouped sub-expression, used in remapped fields. |
| <br> | | <br> | ||
|- | |- | ||
| − | | | + | | ?! |
| − | + | | Not, as in "everything except this". | |
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| <br> | | <br> | ||
|} | |} | ||
| − | <br> | + | <br> Examples<br> |
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Here are some examples: | Here are some examples: | ||
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Add 2720 prefix: | Add 2720 prefix: | ||
| − | /(\d+)/2720\1/ | + | /^(\d+)$/2720\1/ |
or | or | ||
| − | /([0-9]*)/2720\1/ | + | /^([0-9]*)$/2720\1/ |
Strip first 4 digits: | Strip first 4 digits: | ||
| − | /([0-9]{4})([0-9]*)/\2/ | + | /^([0-9]{4})([0-9]*)$/\2/ |
Strip # and 7 first digits: | Strip # and 7 first digits: | ||
| − | /([#])([0-9]{7})([0-9]*)/\3/ | + | /^([#])([0-9]{7})([0-9]*)$/\3/ |
== Web Online Tools == | == Web Online Tools == | ||
| − | *Regular builder tool : [http://www.gskinner.com/RegExr www.gskinner.com/RegExr] | + | *Regular builder tool (with replace) : [http://www.gskinner.com/RegExr www.gskinner.com/RegExr] |
| + | Tips to use: | ||
| + | # No need to enclose the Regular expression with '/'. | ||
| + | # Replace : the regular expression must be split in two parts and '\' replaced by '$'. For example, with '/^([0-9]*)$/2720\1/', the '^([0-9]*)$' would be filled on the first line and '2720$1' on the second line. | ||
| + | |||
*Ruby regular expression editor and tester : [http://rubular.com rubular.com]<br> | *Ruby regular expression editor and tester : [http://rubular.com rubular.com]<br> | ||
== References == | == References == | ||
| − | |||
*[[Toolpack: How to Use RegEx in Remapped Called and Calling Number Mask|How to Use RegEx in Remapped Called and Calling Number Mask]] | *[[Toolpack: How to Use RegEx in Remapped Called and Calling Number Mask|How to Use RegEx in Remapped Called and Calling Number Mask]] | ||
<br> | <br> | ||
Latest revision as of 10:04, 31 January 2014
Quick Reference Table
| Regular Expression Pattern | Explanations | Examples |
|---|---|---|
| Meta characters [\^$.|?*+( |
Special caracters used in regex.
|
|
|
Literal characters |
All characters (except the metacharacters) match a single instance of themselves.
|
/a/ matches "a" |
| [characters] |
Character classes or character set. A character class matches a single character out of all the possibilities offered by the character class. |
/[0-9]/ matches a single digit |
| [\d] |
Shorthand character classes matching digits. Same as [0-9]. |
/[\d]/ matches a single digit |
| . |
Dot matches any characters. |
/a.c/ matches both "a4c" and "ayc" |
| ^ | Matches at the start of the string the regex pattern is applied to. Matches a position rather than a character. | |
| $ | Matches at the end of the string the regex pattern is applied to. Matches a position rather than a character. | |
| {m,n} |
Matches at least “m” and at most “n” occurrences of preceeding character, character class or group. |
|
| * | Matches zero or more occurrences of preceeding character, character class or group. | |
| + | Matches one or more occurrences of preceeding character, character class or group. |
|
| ? | Matches zero or one occurrences of preceeding character, character class or group. | |
| () | Parentheses are used for group or capturing group |
|
| \0, \1, \2, ... | Substitute the value matched by the nth grouped sub-expression, used in remapped fields. | |
| ?! | Not, as in "everything except this". | |
Examples
Here are some examples:
Add 2720 prefix:
/^(\d+)$/2720\1/
or
/^([0-9]*)$/2720\1/
Strip first 4 digits:
/^([0-9]{4})([0-9]*)$/\2/
Strip # and 7 first digits:
/^([#])([0-9]{7})([0-9]*)$/\3/
Web Online Tools
- Regular builder tool (with replace) : www.gskinner.com/RegExr
Tips to use:
- No need to enclose the Regular expression with '/'.
- Replace : the regular expression must be split in two parts and '\' replaced by '$'. For example, with '/^([0-9]*)$/2720\1/', the '^([0-9]*)$' would be filled on the first line and '2720$1' on the second line.
- Ruby regular expression editor and tester : rubular.com
References
