Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Ask a Question
Welcome To Ask or Share your Answers For Others

Categories

javascript - Using querySelectorAll(). Is the result returned by the method ordered?

0 votes
284 views
in Technique[技术] by (71.8m points)

javascript - Using querySelectorAll(). Is the result returned by the method ordered?

I'm trying to make a js code that works with multiple pages. I'm trying to use querySelectorAll() to obtain the elements form the DOM.

I need the elements to be ordered. In order to do that I may use xPath or selectors (I'd prefer to use selectors but xPath is also ok). The problem is:
Are the elements in the NodeList returned by querySelectorAll() ordered against the order that the tags appear in the HTML?

Note: I'd like to add the tag: querySelectorAll

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

The returned node list is ordered. A quick test proved it:

document.querySelectorAll("body, head")[0]; //Returned [object HTMLHeadElement]

Obviously, the <head> tag appears before <body> in a HTML document. The first element of the NodeList is also a <head> element, even if the selector shows body before `head.

From http://www.w3.org/TR/selectors-api/#queryselectorall:

The querySelectorAll() method on the NodeSelector interface must, when invoked, return a NodeList containing all of the matching Element nodes within the node’s subtrees, in document order. If there are no such nodes, the method must return an empty NodeList.


与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

Just Browsing Browsing

2.1m questions

2.1m answers

60 comments

56.9k users

Most popular tags

Powered by Question2Answer
Donate
Theme by Q2A Market&&OStack.cn
...