PHP Regular Expression: How to match all radio buttons in HTML

PHP Regular Expression: How to match all radio button boxes in HTML

In front-end development, we often need to operate and obtain elements in web pages, and in this process, regular expressions Expressions are a very useful tool. In HTML pages, radio button boxes are one of the common elements, and in this article, we will introduce how to use PHP regular expressions to match all radio button boxes.

First of all, we need to know the structure of the radio button in HTML. A simplest radio button usually contains the following elements:

  选项1 

Wherein, thetypeattribute of theelement isradio,nameThe attribute is the name of the radio button group. In the same radio button group, all radio button boxes should have the samenameattribute value, and different radio button boxes should be distinguished by differentvalueattributes.

Next, we can use PHP’spreg_match_all()function to match all radio button boxes. The specific code is as follows:

$pattern = '/]*type="radio"[^>]*>/i'; $matches = array(); preg_match_all($pattern, $html, $matches);

Among them, the regular expression pattern is/]*type="radio"[^>]*>/i, meaning to match allelements with thetype="radio"attribute.preg_match_all()The function will return an array$matches, which contains all matched elements. We can use theprint_r()function to output this array:

print_r($matches);

The output result is as follows:

Array ( [0] => Array ( [0] =>  [1] =>  [2] =>  [3] =>  ) )

As you can see,$matches[0]contains the HTML code of all matching radio button boxes. If we only want to get thenameandvalueattribute values of the radio button, we can modify the regular expression to:

$pattern = '/]*type="radio"[^>]*name="(.+?)"[^>]*value="(.+?)"[^>]*>/i';

where,$matches[ 1]is thenameattribute value of the radio button, and$matches[2]is thevalueattribute value. We can get the attribute values of all radio buttons by looping through the array:

foreach ($matches[0] as $key => $value) { preg_match('/]*type="radio"[^>]*name="(.+?)"[^>]*value="(.+?)"[^>]*>/i', $value, $match); $name = $match[1]; $value = $match[2]; echo "单选框 $key：name = $name, value = $value
"; }

The output result is as follows:

单选框 0：name = radio_group, value = 1 单选框 1：name = radio_group, value = 2 单选框 2：name = radio_group, value = 3 单选框 3：name = other_group, value = 4

In this way, we can use PHP regular expressions to match all radio buttons Frame. Of course, in the actual development process, regular expressions are not omnipotent, and they sometimes cause inaccurate matching. Therefore, we need to use regular expressions carefully according to the specific situation, and we also need to understand some other HTML DOM manipulation methods.

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