Web Front-endJS TutorialWhat is the Hidden Functionality of the \'$\' Variable in Chrome\'s Developer Console?What is the Hidden Functionality of the \'$\' Variable in Chrome\'s Developer Console?
'$' Variable in Chrome: A Native Function with Hidden Functionality
When inspecting the '$' variable in Google Chrome's developer console, you may encounter a native function that is not readily accessible through traditional methods. This puzzling discovery has sparked curiosity among developers, leaving many wondering about its purpose and background.
According to recent updates, the Chrome console has introduced a new definition for '$'. It serves as an alias for various utility functions, including:
- document.querySelector: '$' can be used to retrieve the first matching DOM element based on a CSS selector.
- document.querySelectorAll: '$$' provides an array of all elements that match a CSS selector.
- $_: This variable holds the result of the most recently evaluated expression.
- Historical Element References: '$0', '$1', '$2', '$3', and '$4' refer to the last five elements inspected in the Elements panel or the last five JavaScript heap objects selected in the Profiles panel.
It's important to note that despite the console claiming that '$' is an alias for 'document.querySelector', it actually returns a different result. Additionally, '$$' returns an array rather than the expected NodeList, making its exact behavior somewhat confusing.
Although the 'document.querySelectorAll()' function is not directly accessible through '$', it can be retrieved using '$["querySelectorAll"]()'. This suggests that the native '$' function is more flexible than its apparent equivalence would suggest.
The existence of the '$' variable in Chrome's developer console remains an intriguing aspect of the browser's capabilities. Its versatility and the mystery surrounding its exact functionality make it a fascinating object for further exploration by web developers.
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