Function get_tag($attr, $value, $xml, $tag=null) { if(is_null($tag)) $tag = "\w+"; else $tag = preg_quote($tag); $attr = preg_quote($attr); $value = preg_quote($value); $tag_regex = "/<(".$tag.")[^>]*$attr\s*=\s*". "(["\"])$value\\2[^>]*>(.*?)<\/\\1>/" preg_match_all($tag_regex, $xml, $matches, PREG_PATTERN_ORDER); return $matches; }

Поиск шестнадцатеричных значений цветов

Еще один полезный инструмент для веб-разработчика! Он позволяет вам находить/проверять шестнадцатеричные значение цвета.

$string = "#555555"; if (preg_match("/^#(?:(?:{3}){1,2})$/i", $string)) { echo "example 6 successful."; }

Поиск заголовка статьи

Этот фрагмент кода найдет и выведет на экран текст, находящийся внутри тэгов , на html-странице.

$fp = fopen("http://www.catswhocode.com/blog","r"); while (!feof($fp)){ $page .= fgets($fp, 4096); } $titre = eregi("",$page,$regs); echo $regs; fclose($fp);

Парсинг логов Apache

Большинство сайтов запущено на всем известном веб-сервере Apache. Если ваш сайт находится в их числе, почему бы не использовать PHP и регулярные выражения для разбора логов апача?

//Logs: Apache web server //Successful hits to HTML files only. Useful for counting the number of page views. "^((?#client IP or domain name)S+)s+((?#basic authentication)S+s+S+)s+[((?#date and time)[^]]+)]s+"(?:GET|POST|HEAD) ((?#file)/[^ ?"]+?.html?)??((?#parameters)[^ ?"]+)? HTTP/+"s+(?#status code)200s+((?#bytes transferred)[-0-9]+)s+"((?#referrer)[^"]*)"s+"((?#user agent)[^"]*)"$" //Logs: Apache web server //404 errors only "^((?#client IP or domain name)S+)s+((?#basic authentication)S+s+S+)s+[((?#date and time)[^]]+)]s+"(?:GET|POST|HEAD) ((?#file)[^ ?"]+)??((?#parameters)[^ ?"]+)? HTTP/+"s+(?#status code)404s+((?#bytes transferred)[-0-9]+)s+"((?#referrer)[^"]*)"s+"((?#user agent)[^"]*)"$"

Замена двойных кавычек “умными” кавычками

Если вы любитель типографики, вам понравится это регулярное выражение, заменяющее обычные двойные кавычки, на “умные кавычки”. Похожее регулярное выражение используется в wordpress в контенте страницы.

Preg_replace("B"b([^"x84x93x94rn]+)b"B", "?1?", $text);

Комплексная проверка пароля

Это регулярное выражение будет следить за тем, чтобы в текстовое поле было введено не менее шести символов, цифры, дефисы и подчеркивания.

Текстовое поле должно содержать как минимум один символ верхнего регистра, один нижнего регистра и одну цифру.

"A(?=[-_a-zA-Z0-9]*?)(?=[-_a-zA-Z0-9]*?)(?=[-_a-zA-Z0-9]*?)[-_a-zA-Z0-9]{6,}z"

WordPress: Использование регулярного выражения для получения картинок из записи

Поскольку многие из вас являются пользователями WordPress, вам возможно пригодится код, который позволяет получить все картинки, из текста статьи, и вывести их.

Для того, чтобы использовать этот код, просто вставьте его в любой файл вашей темы.

post_content; $szSearchPattern = "~]* />~"; // Run preg_match_all to grab all the images and save the results in $aPics preg_match_all($szSearchPattern, $szPostContent, $aPics); // Check to see if we have at least 1 image $iNumberOfPics = count($aPics); if ($iNumberOfPics > 0) { // Now here you would do whatever you need to do with the images // For this example the images are just displayed for ($i=0; $i < $iNumberOfPics ; $i++) { echo $aPics[$i]; }; }; endwhile; endif; ?>

Генерация автоматических смайлов

Другая функция, используемая в wordpress – позволяет автоматически заменять символы смайлов на картинку смайла.

$texte="A text with a smiley:-)"; echo str_replace(":-)","",$texte);

Last update on November 27 2019 07:10:59 (UTC/GMT +8 hours)

PHP opening and closing Tags syntax

There are four different pairs of opening and closing tags which can be used in php. Here is the list of tags.

• Default syntax
• Short open Tags
• Omit the PHP closing tag at the end of the file

Default Syntax

The default syntax starts with "".

Example:

Short open Tags

The short tags starts with "". Short style tags are only available when they are enabled in php.ini configuration file on servers.

Example:

Omit the PHP closing tag at the end of the file

It is recommended that a closing PHP tag shall be omitted in a file containing only PHP code so that occurrences of accidental whitespace or new lines being added after the PHP closing tag, which may start output buffering causing uncalled for effects can be avoided.

Example:

PHP Statement separation

In PHP, statements are terminated by a semicolon (;) like C or Perl. The closing tag of a block of PHP code automatically implies a semicolon, there is no need to have a semicolon terminating the last line of a PHP block.

Rules for statement separation

• a semicolon
• AND/OR
• a closing PHP tag

Valid Codes

In the above example, both semicolon(;) and a closing PHP tag are present.

In the above example, there is no semicolon(;) after the last instruction but a closing PHP tag is present.

In the above example, there is a semicolon(;) in the last instruction but there is no closing PHP tag.

PHP Case sensitivity

In PHP the user defined functions, classes, core language keywords (for example if, else, while, echo etc.) are case-insensitive. Therefore the three echo statements in the following example are equal.

Example - 1

"); ECHO("We are learning PHP case sensitivity
"); EcHo("We are learning PHP case sensitivity
"); ?>

We are learning PHP case sensitivity We are learning PHP case sensitivity We are learning PHP case sensitivity

On the other hand, all variables are case-sensitive.

Consider the following example. Only the first statement display the value as $amount because $amount, $AMOUNT, $amoUNT are three different variables.

Example - 2

"); echo("The Amount is: $AMOUNT
"); echo("The Amount is: $amoUNT
"); ?>

The Amount is: 200 The Amount is: The Amount is:

PHP whitespace insensitivity

In general, whitespace is not visible on the screen, including spaces, tabs, and end-of-line characters i.e. carriage returns. In PHP whitespace doesn"t matter in coding. You can break a single line statement to any number of lines or number of separate statements together on a single line.

The following two examples are same:

Example:

"; echo "His Class is: $class and Roll No. is $roll_no"; } student_info("David Rayy", "V", 12) ?>

Example: Advance whitespace insensitivity

"; echo "His Class is: $class and Roll No. is $roll_no"; } student_info("David Rayy", "V", 12) ?>

The Name of student is: David Rayy His Class is: V and Roll No. is 12

Example: Whitespace insensitivity with tabs and spaces

In the following example spaces and tabs are used in a numeric operation, but in both cases, $xyz returns the same value.

"; // tabs and spaces $xyz = 11 + 12; echo $xyz; ?>

PHP: Single line and Multiple lines Comments

Single line comment

PHP supports the following two different way of commenting.

# This is a single line comment.

//This is another way of single line comment.

Example:

Multiple lines comments

PHP supports "C", style comments. A comment starts with the character pair /* and terminates with the character pair */.

/* This is a multiple comment testing,
and these lines will be ignored
at the time of execution */

Example:

Multiple lines comments can not be nested

First PHP Script

Here is the first PHP script which will display "Hello World..." in the web browser.

<?php echo "Hello World..."; ?>

The tags tell the web server to treat everything inside the tags as PHP code to run. The code is very simple. It uses an in-build PHP function "echo" to display the text "Hello World ..." in the web page. Everything outside these tags is sent directly to the browser.

Pictorial presentation

Combining PHP and HTML

PHP syntax is applicable only within PHP tags.

PHP can be embedded in HTML and placed anywhere in the document.

When PHP is embedded in HTML documents and PHP parses this document it interpreted the section enclosed with an opening tag () of PHP and ignore the rest parts of the document.

PHP and HTML are seen together in the following example.

Practice here online: