The tables below are a reference to basic regex. While reading the rest of the site, when in doubt, you can always come back and look here. (It you want a bookmark, here's a direct link to the regex reference tables). I encourage you to print the tables so you have a cheat sheet on your desk for quick reference.
Regex Cheat Sheet tries to provide a basic reference for beginner and advanced developers, lower the entry barrier for newcomers, and help veterans refresh the old tricks. A regular expression (shortened as regex or regexp; also referred to as rational expression) is. Regular Expressions (Regex) Character Classes Cheat Sheet. Character Class. :alpha: Any letter, A-Za-z :upper: Any uppercase letter, A-Z :lower: Any lowercase letter, a-z. Regular Expression Flags; i: Ignore case: m ^ and $ match start and end of line: s. Matches newline as well: x: Allow spaces and comments: J: Duplicate group names allowed: U: Ungreedy quantifiers (?iLmsux) Set flags within regex. Quick-Start: Regex Cheat Sheet. The tables below are a reference to basic regex. While reading the rest of the site, when in doubt, you can always come back and look here. (It you want a bookmark, here's a direct link to the regex reference tables ). I encourage you to print the tables so you have a cheat sheet on your desk for quick reference.
The tables are not exhaustive, for two reasons. First, every regex flavor is different, and I didn't want to crowd the page with overly exotic syntax. For a full reference to the particular regex flavors you'll be using, it's always best to go straight to the source. In fact, for some regex engines (such as Perl, PCRE, Java and .NET) you may want to check once a year, as their creators often introduce new features.
The other reason the tables are not exhaustive is that I wanted them to serve as a quick introduction to regex. If you are a complete beginner, you should get a firm grasp of basic regex syntax just by reading the examples in the tables. I tried to introduce features in a logical order and to keep out oddities that I've never seen in actual use, such as the 'bell character'. With these tables as a jumping board, you will be able to advance to mastery by exploring the other pages on the site.
How to use the tables
The tables are meant to serve as an accelerated regex course, and they are meant to be read slowly, one line at a time. On each line, in the leftmost column, you will find a new element of regex syntax. The next column, 'Legend', explains what the element means (or encodes) in the regex syntax. The next two columns work hand in hand: the 'Example' column gives a valid regular expression that uses the element, and the 'Sample Match' column presents a text string that could be matched by the regular expression.You can read the tables online, of course, but if you suffer from even the mildest case of online-ADD (attention deficit disorder), like most of us… Well then, I highly recommend you print them out. You'll be able to study them slowly, and to use them as a cheat sheet later, when you are reading the rest of the site or experimenting with your own regular expressions.
Enjoy!
If you overdose, make sure not to miss the next page, which comes back down to Earth and talks about some really cool stuff: The 1001 ways to use Regex.
Regex Accelerated Course and Cheat Sheet
For easy navigation, here are some jumping points to various sections of the page:✽ Characters
✽ Quantifiers
✽ More Characters
✽ Logic
✽ More White-Space
✽ More Quantifiers
✽ Character Classes
✽ Anchors and Boundaries
✽ POSIX Classes
✽ Inline Modifiers
✽ Lookarounds
✽ Character Class Operations
✽ Other Syntax
(direct link)
Characters
| Character | Legend | Example | Sample Match |
|---|---|---|---|
| d | Most engines: one digit from 0 to 9 | file_dd | file_25 |
| d | .NET, Python 3: one Unicode digit in any script | file_dd | file_9੩ |
| w | Most engines: 'word character': ASCII letter, digit or underscore | w-www | A-b_1 |
| w | .Python 3: 'word character': Unicode letter, ideogram, digit, or underscore | w-www | 字-ま_۳ |
| w | .NET: 'word character': Unicode letter, ideogram, digit, or connector | w-www | 字-ま‿۳ |
| s | Most engines: 'whitespace character': space, tab, newline, carriage return, vertical tab | asbsc | a b c |
| s | .NET, Python 3, JavaScript: 'whitespace character': any Unicode separator | asbsc | a b c |
| D | One character that is not a digit as defined by your engine's d | DDD | ABC |
| W | One character that is not a word character as defined by your engine's w | WWWWW | *-+=) |
| S | One character that is not a whitespace character as defined by your engine's s | SSSS | Yoyo |
(direct link)
Quantifiers
| Quantifier | Legend | Example | Sample Match |
|---|---|---|---|
| + | One or more | Version w-w+ | Version A-b1_1 |
| {3} | Exactly three times | D{3} | ABC |
| {2,4} | Two to four times | d{2,4} | 156 |
| {3,} | Three or more times | w{3,} | regex_tutorial |
| * | Zero or more times | A*B*C* | AAACC |
| ? | Once or none | plurals? | plural |
(direct link)
More Characters
| Character | Legend | Example | Sample Match |
|---|---|---|---|
| . | Any character except line break | a.c | abc |
| . | Any character except line break | .* | whatever, man. |
| . | A period (special character: needs to be escaped by a ) | a.c | a.c |
| Escapes a special character | .*+? $^/ | .*+? $^/ | |
| Escapes a special character | [{()}] | [{()}] |
(direct link)
Logic
| Logic | Legend | Example | Sample Match |
|---|---|---|---|
| | | Alternation / OR operand | 22|33 | 33 |
| ( … ) | Capturing group | A(nt|pple) | Apple (captures 'pple') |
| 1 | Contents of Group 1 | r(w)g1x | regex |
| 2 | Contents of Group 2 | (dd)+(dd)=2+1 | 12+65=65+12 |
| (?: … ) | Non-capturing group | A(?:nt|pple) | Apple |
(direct link)
More White-Space
| Character | Legend | Example | Sample Match |
|---|---|---|---|
| t | Tab | Ttw{2} | T ab |
| r | Carriage return character | see below | |
| n | Line feed character | see below | |
| rn | Line separator on Windows | ABrnCD | AB CD |
| N | Perl, PCRE (C, PHP, R…): one character that is not a line break | N+ | ABC |
| h | Perl, PCRE (C, PHP, R…), Java: one horizontal whitespace character: tab or Unicode space separator | ||
| H | One character that is not a horizontal whitespace | ||
| v | .NET, JavaScript, Python, Ruby: vertical tab | ||
| v | Perl, PCRE (C, PHP, R…), Java: one vertical whitespace character: line feed, carriage return, vertical tab, form feed, paragraph or line separator | ||
| V | Perl, PCRE (C, PHP, R…), Java: any character that is not a vertical whitespace | ||
| R | Perl, PCRE (C, PHP, R…), Java: one line break (carriage return + line feed pair, and all the characters matched by v) |
(direct link)
More Quantifiers
| Quantifier | Legend | Example | Sample Match |
|---|---|---|---|
| + | The + (one or more) is 'greedy' | d+ | 12345 |
| ? | Makes quantifiers 'lazy' | d+? | 1 in 12345 |
| * | The * (zero or more) is 'greedy' | A* | AAA |
| ? | Makes quantifiers 'lazy' | A*? | empty in AAA |
| {2,4} | Two to four times, 'greedy' | w{2,4} | abcd |
| ? | Makes quantifiers 'lazy' | w{2,4}? | ab in abcd |
(direct link)
Character Classes
| Character | Legend | Example | Sample Match |
|---|---|---|---|
| [ … ] | One of the characters in the brackets | [AEIOU] | One uppercase vowel |
| [ … ] | One of the characters in the brackets | T[ao]p | Tap or Top |
| - | Range indicator | [a-z] | One lowercase letter |
| [x-y] | One of the characters in the range from x to y | [A-Z]+ | GREAT |
| [ … ] | One of the characters in the brackets | [AB1-5w-z] | One of either: A,B,1,2,3,4,5,w,x,y,z |
| [x-y] | One of the characters in the range from x to y | [ -~]+ | Characters in the printable section of the ASCII table. |
| [^x] | One character that is not x | [^a-z]{3} | A1! |
| [^x-y] | One of the characters not in the range from x to y | [^ -~]+ | Characters that are not in the printable section of the ASCII table. |
| [dD] | One character that is a digit or a non-digit | [dD]+ | Any characters, inc- luding new lines, which the regular dot doesn't match |
| [x41] | Matches the character at hexadecimal position 41 in the ASCII table, i.e. A | [x41-x45]{3} | ABE |
(direct link)
Anchors and Boundaries
| Anchor | Legend | Example | Sample Match |
|---|---|---|---|
| ^ | Start of string or start of line depending on multiline mode. (But when [^inside brackets], it means 'not') | ^abc .* | abc (line start) |
| $ | End of string or end of line depending on multiline mode. Many engine-dependent subtleties. | .*? the end$ | this is the end |
| A | Beginning of string (all major engines except JS) | Aabc[dD]* | abc (string... ...start) |
| z | Very end of the string Not available in Python and JS | the endz | this is...n...the end |
| Z | End of string or (except Python) before final line break Not available in JS | the endZ | this is...n...the endn |
| G | Beginning of String or End of Previous Match .NET, Java, PCRE (C, PHP, R…), Perl, Ruby | ||
| b | Word boundary Most engines: position where one side only is an ASCII letter, digit or underscore | Bob.*bcatb | Bob ate the cat |
| b | Word boundary .NET, Java, Python 3, Ruby: position where one side only is a Unicode letter, digit or underscore | Bob.*bкошкаb | Bob ate the кошка |
| B | Not a word boundary | c.*BcatB.* | copycats |
(direct link)
POSIX Classes
| Character | Legend | Example | Sample Match |
|---|---|---|---|
| [:alpha:] | PCRE (C, PHP, R…): ASCII letters A-Z and a-z | [8[:alpha:]]+ | WellDone88 |
| [:alpha:] | Ruby 2: Unicode letter or ideogram | [[:alpha:]d]+ | кошка99 |
| [:alnum:] | PCRE (C, PHP, R…): ASCII digits and letters A-Z and a-z | [[:alnum:]]{10} | ABCDE12345 |
| [:alnum:] | Ruby 2: Unicode digit, letter or ideogram | [[:alnum:]]{10} | кошка90210 |
| [:punct:] | PCRE (C, PHP, R…): ASCII punctuation mark | [[:punct:]]+ | ?!.,:; |
| [:punct:] | Ruby: Unicode punctuation mark | [[:punct:]]+ | ‽,:〽⁆ |
Inline Modifiers
None of these are supported in JavaScript. In Ruby, beware of (?s) and (?m).| Modifier | Legend | Example | Sample Match |
|---|---|---|---|
| (?i) | Case-insensitive mode (except JavaScript) | (?i)Monday | monDAY |
| (?s) | DOTALL mode (except JS and Ruby). The dot (.) matches new line characters (rn). Also known as 'single-line mode' because the dot treats the entire input as a single line | (?s)From A.*to Z | From A to Z |
| (?m) | Multiline mode (except Ruby and JS) ^ and $ match at the beginning and end of every line | (?m)1rn^2$rn^3$ | 1 2 3 |
| (?m) | In Ruby: the same as (?s) in other engines, i.e. DOTALL mode, i.e. dot matches line breaks | (?m)From A.*to Z | From A to Z |
| (?x) | Free-Spacing Mode mode (except JavaScript). Also known as comment mode or whitespace mode | (?x) # this is a # comment abc # write on multiple # lines [ ]d # spaces must be # in brackets | abc d |
| (?n) | .NET, PCRE 10.30+: named capture only | Turns all (parentheses) into non-capture groups. To capture, use named groups. | |
| (?d) | Java: Unix linebreaks only | The dot and the ^ and $ anchors are only affected by n | |
| (?^) | PCRE 10.32+: unset modifiers | Unsets ismnx modifiers |
(direct link)
Lookarounds
| Lookaround | Legend | Example | Sample Match |
|---|---|---|---|
| (?=…) | Positive lookahead | (?=d{10})d{5} | 01234 in 0123456789 |
| (?<=…) | Positive lookbehind | (?<=d)cat | cat in 1cat |
| (?!…) | Negative lookahead | (?!theatre)thew+ | theme |
| (? | Negative lookbehind | w{3}(? | Munster |
(direct link)
Character Class Operations
| Class Operation | Legend | Example | Sample Match |
|---|---|---|---|
| […-[…]] | .NET: character class subtraction. One character that is in those on the left, but not in the subtracted class. | [a-z-[aeiou]] | Any lowercase consonant |
| […-[…]] | .NET: character class subtraction. | [p{IsArabic}-[D]] | An Arabic character that is not a non-digit, i.e., an Arabic digit |
| […&&[…]] | Java, Ruby 2+: character class intersection. One character that is both in those on the left and in the && class. | [S&&[D]] | An non-whitespace character that is a non-digit. |
| […&&[…]] | Java, Ruby 2+: character class intersection. | [S&&[D]&&[^a-zA-Z]] | An non-whitespace character that a non-digit and not a letter. |
| […&&[^…]] | Java, Ruby 2+: character class subtraction is obtained by intersecting a class with a negated class | [a-z&&[^aeiou]] | An English lowercase letter that is not a vowel. |
| […&&[^…]] | Java, Ruby 2+: character class subtraction | [p{InArabic}&&[^p{L}p{N}]] | An Arabic character that is not a letter or a number |
(direct link)
Other Syntax
| Syntax | Legend | Example | Sample Match |
|---|---|---|---|
| K | Keep Out Perl, PCRE (C, PHP, R…), Python's alternate regex engine, Ruby 2+: drop everything that was matched so far from the overall match to be returned | prefixKd+ | 12 |
| Q…E | Perl, PCRE (C, PHP, R…), Java: treat anything between the delimiters as a literal string. Useful to escape metacharacters. | Q(C++ ?)E | (C++ ?) |
and The Best Regex Trick Ever!!!
The 1001 ways to use Regex
Thankyou very much for compiling these. I am new to text analytics and is struggling a lot with regex. This is helping me a lot pick up. Great work
Regular Expression Cheat Sheet Mit
Regular expressions are a very useful tool for developers. They allow to find, identify or replace a word, character or any kind of string. This tutorial will teach you how to master PHP regexp and show you extremely useful, ready-to-use PHP regular expressions that any web developer should have in his toolkit.
Getting Started With Regular Expressions
Regular Expression Cheat Sheet R
For many beginners, regular expressions seem to be hard to learn and use. In fact, they're far less hard than you may think. Before we dive deep inside regexp with useful and reusable codes, let's quickly see the basics of PCRE regex patterns:
Regular Expressions Syntax
A regular expression (regex or regexp for short) is a special text string for describing a search pattern. A regex pattern matches a target string. The following table describes most common regex:
| Regular Expression | Will match… |
|---|---|
| foo | The string 'foo' |
| ^foo | 'foo' at the start of a string |
| foo$ | 'foo' at the end of a string |
| ^foo$ | 'foo' when it is alone on a string |
| [abc] | a, b, or c |
| [a-z] | Any lowercase letter |
| [^A-Z] | Any character that is not a uppercase letter |
| (gif|jpg) | Matches either 'gif' or 'jpg' |
| [a-z]+ | One or more lowercase letters |
| [0-9.-] | Any number, dot, or minus sign |
| ^[a-zA-Z0-9_]{1,}$ | Any word of at least one letter, number or _ |
| ([wx])([yz]) | wy, wz, xy, or xz |
| [^A-Za-z0-9] | Any symbol (not a number or a letter) |
| ([A-Z]{3}|[0-9]{4}) | Matches three letters or four numbers |
PHP Regular Expression Functions
PHP has many useful functions to work with regular expressions. Here is a quick cheat sheet of the main PHP regex functions. Remember that all of them are case sensitive.
For more information about the native functions for PHP regular expressions, have a look at the manual.
| Function | Description |
|---|---|
| preg_match() | The preg_match() function searches string for pattern, returning true if pattern exists, and false otherwise. |
| preg_match_all() | The preg_match_all() function matches all occurrences of pattern in string. Useful for search and replace. |
| preg_replace() | The preg_replace() function operates just like ereg_replace(), except that regular expressions can be used in the pattern and replacement input parameters. |
| preg_split() | Preg Split (preg_split()) operates exactly like the split() function, except that regular expressions are accepted as input parameters. |
| preg_grep() | The preg_grep() function searches all elements of input_array, returning all elements matching the regex pattern within a string. |
| preg_ quote() | Quote regular expression characters |
Validate a Domain Name
Case sensitive regex to verify if a string is a valid domain name. This is very useful when validating web forms.
» Source
Enlight a Word From a Text
This very useful regular expression will find a specific word in a string and enlight it. Extremely useful for search results. Remember that it's case sensitive.
» Source
Enlight Search Results in Your WordPress Blog
The previous code snippet can be very handy when it comes to displaying search results. If your website is powered by WordPress, here is a more specific snippet that will search and replace a text by the same text within an HTML tag that you can style later, using CSS.
Open your search.php file and find the the_title() function. Replace it with the following:
Now, just before the modified line, add this code:
Save the search.php file and open style.css. Append the following line to it:
» Source
Get All Images From a HTML Document
If you ever wanted to be able to get all images form a webpage, this code is a must have for you. You should easily create an image downloader using the power of cURL.
» Source
Remove Repeated Words (Case Insensitive)
Often repeating words while typing? This handy case insensitive PCRE regex will be very helpful.
» Source
Remove Repeated Punctuation
Same php regex as above, but this one will look for repeated punctuation within a string. Goodbye multiple commas!
» Source
Match a XML/HTML Tag
Inline Modifiers
None of these are supported in JavaScript. In Ruby, beware of (?s) and (?m).| Modifier | Legend | Example | Sample Match |
|---|---|---|---|
| (?i) | Case-insensitive mode (except JavaScript) | (?i)Monday | monDAY |
| (?s) | DOTALL mode (except JS and Ruby). The dot (.) matches new line characters (rn). Also known as 'single-line mode' because the dot treats the entire input as a single line | (?s)From A.*to Z | From A to Z |
| (?m) | Multiline mode (except Ruby and JS) ^ and $ match at the beginning and end of every line | (?m)1rn^2$rn^3$ | 1 2 3 |
| (?m) | In Ruby: the same as (?s) in other engines, i.e. DOTALL mode, i.e. dot matches line breaks | (?m)From A.*to Z | From A to Z |
| (?x) | Free-Spacing Mode mode (except JavaScript). Also known as comment mode or whitespace mode | (?x) # this is a # comment abc # write on multiple # lines [ ]d # spaces must be # in brackets | abc d |
| (?n) | .NET, PCRE 10.30+: named capture only | Turns all (parentheses) into non-capture groups. To capture, use named groups. | |
| (?d) | Java: Unix linebreaks only | The dot and the ^ and $ anchors are only affected by n | |
| (?^) | PCRE 10.32+: unset modifiers | Unsets ismnx modifiers |
(direct link)
Lookarounds
| Lookaround | Legend | Example | Sample Match |
|---|---|---|---|
| (?=…) | Positive lookahead | (?=d{10})d{5} | 01234 in 0123456789 |
| (?<=…) | Positive lookbehind | (?<=d)cat | cat in 1cat |
| (?!…) | Negative lookahead | (?!theatre)thew+ | theme |
| (? | Negative lookbehind | w{3}(? | Munster |
(direct link)
Character Class Operations
| Class Operation | Legend | Example | Sample Match |
|---|---|---|---|
| […-[…]] | .NET: character class subtraction. One character that is in those on the left, but not in the subtracted class. | [a-z-[aeiou]] | Any lowercase consonant |
| […-[…]] | .NET: character class subtraction. | [p{IsArabic}-[D]] | An Arabic character that is not a non-digit, i.e., an Arabic digit |
| […&&[…]] | Java, Ruby 2+: character class intersection. One character that is both in those on the left and in the && class. | [S&&[D]] | An non-whitespace character that is a non-digit. |
| […&&[…]] | Java, Ruby 2+: character class intersection. | [S&&[D]&&[^a-zA-Z]] | An non-whitespace character that a non-digit and not a letter. |
| […&&[^…]] | Java, Ruby 2+: character class subtraction is obtained by intersecting a class with a negated class | [a-z&&[^aeiou]] | An English lowercase letter that is not a vowel. |
| […&&[^…]] | Java, Ruby 2+: character class subtraction | [p{InArabic}&&[^p{L}p{N}]] | An Arabic character that is not a letter or a number |
(direct link)
Other Syntax
| Syntax | Legend | Example | Sample Match |
|---|---|---|---|
| K | Keep Out Perl, PCRE (C, PHP, R…), Python's alternate regex engine, Ruby 2+: drop everything that was matched so far from the overall match to be returned | prefixKd+ | 12 |
| Q…E | Perl, PCRE (C, PHP, R…), Java: treat anything between the delimiters as a literal string. Useful to escape metacharacters. | Q(C++ ?)E | (C++ ?) |
and The Best Regex Trick Ever!!!
The 1001 ways to use Regex
Thankyou very much for compiling these. I am new to text analytics and is struggling a lot with regex. This is helping me a lot pick up. Great work
Regular Expression Cheat Sheet Mit
Regular expressions are a very useful tool for developers. They allow to find, identify or replace a word, character or any kind of string. This tutorial will teach you how to master PHP regexp and show you extremely useful, ready-to-use PHP regular expressions that any web developer should have in his toolkit.
Getting Started With Regular Expressions
Regular Expression Cheat Sheet R
For many beginners, regular expressions seem to be hard to learn and use. In fact, they're far less hard than you may think. Before we dive deep inside regexp with useful and reusable codes, let's quickly see the basics of PCRE regex patterns:
Regular Expressions Syntax
A regular expression (regex or regexp for short) is a special text string for describing a search pattern. A regex pattern matches a target string. The following table describes most common regex:
| Regular Expression | Will match… |
|---|---|
| foo | The string 'foo' |
| ^foo | 'foo' at the start of a string |
| foo$ | 'foo' at the end of a string |
| ^foo$ | 'foo' when it is alone on a string |
| [abc] | a, b, or c |
| [a-z] | Any lowercase letter |
| [^A-Z] | Any character that is not a uppercase letter |
| (gif|jpg) | Matches either 'gif' or 'jpg' |
| [a-z]+ | One or more lowercase letters |
| [0-9.-] | Any number, dot, or minus sign |
| ^[a-zA-Z0-9_]{1,}$ | Any word of at least one letter, number or _ |
| ([wx])([yz]) | wy, wz, xy, or xz |
| [^A-Za-z0-9] | Any symbol (not a number or a letter) |
| ([A-Z]{3}|[0-9]{4}) | Matches three letters or four numbers |
PHP Regular Expression Functions
PHP has many useful functions to work with regular expressions. Here is a quick cheat sheet of the main PHP regex functions. Remember that all of them are case sensitive.
For more information about the native functions for PHP regular expressions, have a look at the manual.
| Function | Description |
|---|---|
| preg_match() | The preg_match() function searches string for pattern, returning true if pattern exists, and false otherwise. |
| preg_match_all() | The preg_match_all() function matches all occurrences of pattern in string. Useful for search and replace. |
| preg_replace() | The preg_replace() function operates just like ereg_replace(), except that regular expressions can be used in the pattern and replacement input parameters. |
| preg_split() | Preg Split (preg_split()) operates exactly like the split() function, except that regular expressions are accepted as input parameters. |
| preg_grep() | The preg_grep() function searches all elements of input_array, returning all elements matching the regex pattern within a string. |
| preg_ quote() | Quote regular expression characters |
Validate a Domain Name
Case sensitive regex to verify if a string is a valid domain name. This is very useful when validating web forms.
» Source
Enlight a Word From a Text
This very useful regular expression will find a specific word in a string and enlight it. Extremely useful for search results. Remember that it's case sensitive.
» Source
Enlight Search Results in Your WordPress Blog
The previous code snippet can be very handy when it comes to displaying search results. If your website is powered by WordPress, here is a more specific snippet that will search and replace a text by the same text within an HTML tag that you can style later, using CSS.
Open your search.php file and find the the_title() function. Replace it with the following:
Now, just before the modified line, add this code:
Save the search.php file and open style.css. Append the following line to it:
» Source
Get All Images From a HTML Document
If you ever wanted to be able to get all images form a webpage, this code is a must have for you. You should easily create an image downloader using the power of cURL.
» Source
Remove Repeated Words (Case Insensitive)
Often repeating words while typing? This handy case insensitive PCRE regex will be very helpful.
» Source
Remove Repeated Punctuation
Same php regex as above, but this one will look for repeated punctuation within a string. Goodbye multiple commas!
» Source
Match a XML/HTML Tag
This simple function takes two arguments: The first is the tag you'd like to match, and the second is the variable containing the XML or HTML. Once again, this can be very powerful used along with cURL.
Match an HTML/XML Tag With a Specific Attribute Value
This function is very similar to the previous one, but it allow you to match a tag having a specific attribute. For example, you could easily match
Match Hexadecimal Color Values
Another interesting tool for web developers! It allows you to match/validate a hexadecimal color value.
Find Page Title
This handy code snippet will find and print the text within the </code> and <code> tags of a HTML page.
Parse Apache Logs
Most websites are running on the Apache webserver. If your website does, you can easily use PHP and regular expressions to parse Apache logs.
» Source
Replace Double Quotes by Smart Quotes
If you're a typography lover, you'll probably love this regex pattern which allow you to replace double quotes by smart quotes. A similar regular expression is used by WordPress to make the content more beautiful.
» Source
Check Password Complexity
This regular expression will tests if the input consists of 6 or more letters, digits, underscores, and hyphens.
The input must contain at least one uppercase letter, one lowercase letter and one digit.
» Source
WordPress: Using Regexp to Retrieve Images From a Post
As I know many of you are WordPress users, you'll probably enjoy that code which allows you to retrieve all images from post content and display it.
To use this code on your blog, simply paste the following code on one of your theme files.
Generate Emoticons Automatically
Another function used by WordPress. This one allow you to automatically replace an emoticon symbol by an image.
