PHP supports 3 styles of comments
1.C style (//) comments
This kind of comment cannot appear in the ?> tag. If the short_open and asp_tag settings are turned on, > and %> also cannot appear in the comment
<?<span>php </span><span>echo</span> 'Hello,PHP!'; <span>//</span><span>我是注释,不被执行 </span> ?>
2.C language style, nested comments are not allowed
<?<span>php </span><span>/*</span><span> *我是注释,不被执行 </span><span>*/</span> <span>echo</span> ‘Hello,PHP!<span>’; </span>?>
3.Shell style, same as C ban
<?<span>php </span><span>echo</span> 'Hello,PHP!'; <span>#</span><span>我是注释,不被执行</span> ?>