HTML-ENTITIES encoding

When using fabpot/goutte (https://github.com/FriendsOfPHP/Goutte) to crawl the web page, I found that no matter what encoding the target page is (gb2312...), the final result is unicode.
After research, I found that Symfony’s crawler calls html-entities encoding.

mb_convert_encoding($content, 'HTML-ENTITIES', $charset);

Then, the basic knowledge was popularized on Wikipedia. . . html-entities are encoded using unicode (http://en.wikipedia.org/wiki/Character_encodings_in_HTML).

Reference

A numeric character reference in HTML refers to a character by its Universal Character Set/Unicode code point

Hereby recorded.

The above introduces HTML-ENTITIES coding, including aspects of content. I hope it will be helpful to friends who are interested in PHP tutorials.