How to remove HTML tags in PHP using regular expressions

In web development, HTML is an essential element. But sometimes we need to extract plain text from HTML without HTML tags. At this time, regular expressions are a very convenient tool.

In PHP, you can use the preg_replace() function to remove HTML tags. The usage of this function is as follows:

preg_replace($pattern, $replacement, $subject);

Among them, $pattern is the regular expression pattern, $replacement is the replacement string, and $subject is the string to be processed. Note that both $pattern and $replacement can be arrays, as discussed below.

Next, we will discuss several common regular expressions for removing HTML tags.

1. Remove HTML tags

$pattern = '/<[^>]*>/';
$replacement = '';
$text = preg_replace($pattern, $replacement, $html);

In this regular expression, 5925c7a0fdcc92720851b182a2063e00 tag and remove it. The (?s) token means . matches any character, including newlines. This expression is also non-greedy because it uses *?, which will match as few characters as possible.

3. Remove style tags

$pattern = '/<style[^>]*>(.*?)</style>/is';
$replacement = '';
$text = preg_replace($pattern, $replacement, $html);

This regular expression will match any text with a c9ccee2e6ea535a969eb3f532ad9fe89 tag and remove it. (?s) markers and *? are used in a similar manner to the previous example.

4. Remove empty tags

$pattern = '/<([a-z]+)(?:s+[^>]+)?>(s*)</
>/i';
$replacement = '';
$text = preg_replace($pattern, $replacement, $html);

This regular expression will match any empty tags and remove them. (s*) will match any whitespace character. ?: represents a non-capturing group, meaning it will be matched but not replaced.

5. Remove unnecessary whitespace characters

$pattern = '/>s+</';
$replacement = '><';
$text = preg_replace($pattern, $replacement, $html);

This simple regex will match any whitespace character between two tags and replace it with a single space .

To sum up, these regular expressions are often used when removing HTML tags. Of course, there are many ways to remove HTML tags. The final choice depends on your specific needs and how your code is implemented.

---

1. > ↩

The above is the detailed content of How to remove HTML tags in PHP using regular expressions. For more information, please follow other related articles on the PHP Chinese website!