不成对的 HTML tag

2017-12-28 本文已影响5人成江

<br>
If you are outputting HTML on a regular website you can use <br> or <br/> , both are valid anytime you are serving HTML5 as text/html. If you are serving HTML5 as XHTML (i.e. content type application/xhtml+xml, with an XML declaration) then you must use a self closing tag like so: <br/>
<hr>
In HTML5, the <hr> tag defines a thematic break.
In HTML 4.01, the <hr> tag represents a horizontal rule.
However, the <hr> tag may still be displayed as a horizontal rule in visual browsers.