Definition and Usage
The querySelectorAll() method returns all elements in the document that matches a specified CSS selector(s), as a static NodeList object.
The NodeList object represents a collection of nodes. The nodes can be accessed by index numbers. The index starts at 0.
Tip: You can use the length property of the NodeList object to determine the number of elements that match the specified selector, then you can loop through all elements and extract the info you want. A NodeList object is a list (collection) of nodes extracted from a document.
A NodeList object is almost the same as an HTMLCollection object.
Some (older) browsers return a NodeList object instead of an HTMLCollection for methods like getElementsByClassName().
All browsers return a NodeList object for the property childNodes.
Most browsers return a NodeList object for the method querySelectorAll().
HTML DOM Node List Length
The length property defines the number of nodes in a node list:
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