问题
How is correct to write the br tag in html?
<br />
or
<br>
or anything else? :))
回答1:
It depends on the doctype you're using. In the original versions of HTML (up to HTML4), only <br> is correct. In XHTML (which is based on XML), only <br /> is correct. In HTML5, both are allowed although <br> is preferred.
回答2:
It does not need an end tag, so
<br>
is correct for HTML, and
<br />
for XHTML.
回答3:
In HTML4.01 or earlier, it is <br>. This is case-insensitive, and whitespace between the r and the > is ignored.
In all forms of XHTML it is <br/>. This is case-sensitive, and again whitespace between the r and the /> is ignored. <br></br> is also allowed, but unusual (there are backwards-compatibility issues, it's extra typing, and allows for bugs if you introduce more content between the tags by mistake, but it does sometimes happen in XML-programattically produced code).
Since some earlier browsers that would parse XHTML as earlier HTML would choke on <br/> but not on <br /> such extra whitespace is the norm, for backwards compatibility (more backwards kludging it, but still...).
In HTML5 either are allowed (but not <br></br>).
回答4:
@CIRK: HTML4, <br>. XHTML 1.x, <br />. <br/> is also acceptable.
回答5:
You should use <br /> because it respect the standards XHTML, HTML and in general (XML). Because every xml tag needs to close.
回答6:
In HTML (up to version 4) it's <br>And in XHTML it's <br /> because the tag has to be properly closed with an /
HTML5 <br> is the best option.
回答7:
it is most formal to use <br/>
this is then XHTML compliant - all opening tags have corresponding end tag.
回答8:
<br/>.
Here:
Some of the most common errors in the usage of XHTML are:
Not closing empty elements (elements without closing tags in HTML4)
Incorrect: <br>
Correct: <br />
Note that any of these is acceptable in XHTML: <br></br>, <br/>, and <br />. Older HTML-only browsers interpreting it as HTML will generally accept <br> and <br />.
来源：https://stackoverflow.com/questions/4288460/html-whats-the-correct-form-of-br