event.preventDefault() Vs. return false

By: Rajesh P.S.

The return false; and e.preventDefault(); are both commonly used in JavaScript and jQuery to prevent default actions in response to events. However, they have some differences in how they work and when they are typically used:

return false;

When used within an event handler function, such as a click event handler, return false; essentially combines three actions: e.preventDefault();, e.stopPropagation();, and return false;.

It prevents the default behavior of an event (e.g., prevents a form from submitting, prevents a link from navigating to a new page), stops the event from propagating to parent elements (bubbling), and exits the function early, preventing any code below it from executing.

$("#myButton").click(function() { // Prevent the default behavior of the button click // and stop event propagation alert("Button clicked!"); return false; });

e.preventDefault();

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e.preventDefault(); is a method specifically for preventing the default behavior of an event object (e) in JavaScript. It only prevents the default action associated with the event, such as submitting a form or following a link, without affecting event propagation or exiting the function.

$("#myLink").click(function(e) { // Prevent the default behavior of the link click e.preventDefault(); alert("Link clicked, but no navigation occurred."); });

event.preventDefault() Vs. return false

Event Propagation: return false; stops event propagation (bubbling) in addition to preventing the default action, while e.preventDefault(); only prevents the default action and allows event propagation to continue.
Function Flow: return false; exits the entire function where it's used, while e.preventDefault(); allows the function to continue executing after preventing the default action.

Conclusion

In most cases, if you only need to prevent the default behavior of an event (e.g., prevent a link from navigating), using e.preventDefault(); is the recommended approach because it's more explicit and doesn't interfere with event propagation or function flow. return false; is often used in legacy code or for situations where you want to prevent both the default action and event propagation and exit the function early.

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