In our project, there is a different functionality when one Dollar sign used $() in Chrome console vs two Dollar signs $$(), besides the known difference that $$() return an array an $() return the first element.
For example, selector for specific element, with one dollar and two dollar queries:
$$(".my-class[my-attribute='trump']") //works
$('.my-class[my-attribute=sanders]') //works
$$('.my-class[my-attribute=trump]') //not work
What is the source and explanation for this behavior?
$ is an alias for document. querySelector . In the same vein there is $$ which is an alias for document. querySelectorAll . It is defined in the Command line (console) api.
$ – dollar identifier The dollar ($) sign is a JavaScript identifier, which simply means that it identifies an object in the same way that a name or variable does. Variables, functions, properties, events, and objects can be identified by the $ sign.
To open the Command Menu: Press Control + Shift + P (Windows / Linux) or Command + Shift + P (Mac). Click. Customize and control DevTools and then select Run command.
The $ sign is nothing but an identifier of jQuery() function. Instead of writing jQuery we simply write $ which is the same as jQuery() function. A $ with a selector specifies that it is a jQuery selector.
From Chrome Developer Tools documentation:
Selecting Elements
There are a few shortcuts for selecting elements. These save you valuable time when compared to typing out their standard counterparts.
$() Returns the first element that matches the specified CSS selector. It is a shortcut for document.querySelector().
$$() Returns an array of all the elements that match the specified CSS selector. This is an alias for document.querySelectorAll()
$x() Returns an array of elements that match the specified XPath.
When you use querySelector
(or $
), the result is an element or null
. When you use $$
, the result isn't an element but an Array
which can be easily iterated over. This differs from the native querySelectorAll
where it returns a NodeList
which is slightly harder to go over all the entries.
Regarding the quote: of course it works the same. See:
Conclusion: It's useless to quote trump
. You might also end insane.
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