How to remove HTML tags in php

PHP is a popular scripting language which is widely used for website development. When developing a website, it is often necessary to obtain data from the database and display it on the web page. However, the text obtained from the database is not necessarily plain text. Sometimes it contains HTML tags, such as

,

, , etc.

These tags may interfere with the layout and display of the website, so sometimes these tags need to be removed. PHP provides some functions and methods that can help us remove HTML tags. Here are some commonly used methods.

Method 1: strip_tags() function

The strip_tags() function is a built-in function of PHP that can help us remove HTML tags.

Its syntax is as follows:

strip_tags(string $str, string $allowable_tags)

Among them, $str is the string to remove HTML tags, $allowable_tags optional parameter is a string containing allowed tags, other tags will be removed. If $allowable_tags is not specified, all HTML tags will be stripped. The following is an example:

$str = "<p>这是一段带有HTML标签的文本。</p>";
echo strip_tags($str);

The output is:

这是一段带有HTML标签的文本。

As you can see, the strip_tags() function successfully removes the HTML tags.

Method 2: Use regular expressions

Regular expressions can also help us remove HTML tags. The following is an example of using regular expressions:

$str = "<p>这是一段带有HTML标签的文本。</p>";
echo preg_replace(&#39;/<[^>]*>/&#39;, &#39;&#39;, $str);

The output is:

这是一段带有HTML标签的文本。

In this example, we use the preg_replace() function, the first parameter is a regular expression, used Matches all HTML tags. This regular expression means to match a string containing 0 or more non-> characters after < and then replace it with an empty string. The second parameter is the string to be replaced, that is, the string from which the HTML tags are to be removed.

Method 3: Use the DOMDocument class

In PHP, we can also use the DOMDocument class to remove HTML tags.

The DOMDocument class is a built-in class of PHP that can be used to process XML and HTML documents.

The following is an example of using the DOMDocument class:

$str = "<p>这是一段带有HTML标签的文本。</p>";
$dom = new DOMDocument();
$dom->loadHTML($str);
echo $dom->textContent;

The output is:

这是一段带有HTML标签的文本。

In this example, we first create a DOMDocument object and then use its loadHTML() Method to load a string with HTML tags removed. Finally, use the textContent property to get the plain text content without HTML tags.

Summary

This article introduces three commonly used methods to help us remove HTML tags.

• The strip_tags() function can remove all HTML tags or keep only certain specified tags.

• Using regular expressions can match and replace HTML tags more flexibly.

• Using the DOMDocument class can help us easily obtain plain text content that does not contain HTML tags. Which method to choose depends on the situation.

If you only need to remove all HTML tags, the strip_tags() function may be the simplest and most suitable choice. If you need to more flexibly control which HTML tags to remove, you can use regular expressions. If you need to process more complex HTML documents, it may be more convenient to use the DOMDocument class.

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