HTML5 Tips: Obtain the head element through document.head_html5 Tutorial Tips

Today, I looked at a foreign website and found that the head element is obtained as follows

Copy code

The code is as follows:

var head = document.head || document .getElementsByTagName('head')[0];

The latter is our commonly used method, and the previous document.head is actually the first time we see it. After checking the information, I found that it turned out to be HTML5 stuff. It's really simple, just one attribute.

Of course, IE6/7/8 does not support it. IE9/Safari/Chrome/FF/Opera are all supported (latest version). Record it.

The HTMLDocument interface in html4 is as follows

The HTMLDocument interface in html5 is as follows

Related:

http://www.w3.org/TR/DOM-Level-2-HTML/html.html#ID-26809268

http://www.w3.org/TR/html5/dom.html#html-documents

http://msdn.microsoft.com/en-us/library/gg593004(v=VS.85)