How to determine equality for two JavaScript objects?

javascript object equals hashcode
user4903 picture user4903 · Oct 14, 2008 · Viewed 540.6k times · Source

A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java?

Stack Overflow question Is there any kind of hashCode function in JavaScript? is similar to this question, but requires a more academic answer. The scenario above demonstrates why it would be necessary to have one, and I'm wondering if there is any equivalent solution.

Answer

coolaj86 picture coolaj86 · Jul 7, 2010

Why reinvent the wheel? Give Lodash a try. It has a number of must-have functions such as isEqual().

_.isEqual(object, other);

It will brute force check each key value - just like the other examples on this page - using ECMAScript 5 and native optimizations if they're available in the browser.

Note: Previously this answer recommended Underscore.js, but lodash has done a better job of getting bugs fixed and addressing issues with consistency.

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