[HTML5 and CSS3 Basics] selector querySelector and querySelectorAll, css3queryselector

[HTML5 and CSS3 Basics] selector querySelector and querySelectorAll, css3queryselector

HTML5 provides two selector functions similar to JQuery for searching elements: querySelector and querySelectorAll. The former searches for elements and returns the first element, while the latter searches for elements and returns a NodeList, it contains all elements that match the selector.
Usage:
Var buttons = document. querySelectorAll (". menu ");
The preceding statement finds the elements whose class is menu and whose label is a, forms an array, and assigns values to buttons. Then, you can use the array to use the searched elements.
The parameters of the above two methods must use the selection Syntax of CSS3. For the selection Syntax of CSS3, refer to this address: CSS selector reference manual.

The preceding example uses the following selection Syntax: