How do I iterate over objects in JavaScript?

How do I iterate over objects in JavaScript?

You can use several methods like for...in, Object.keys(), or Object.entries() to iterate over objects.

Can you show me an example using Object.keys()?

Sure! Here's an example:

const obj = { a: 1, b: 2, c: 3 };
Object.keys(obj).forEach(key => {
    console.log(key, obj[key]);
});

What about using for...in? Is it different?

Yes, for...in iterates over all enumerable properties. Here's how you can use it:

for (let key in obj) {
    console.log(key, obj[key]);
}

Are there any performance differences between these methods?

Yes, for...in can be slower for large objects, while Object.keys() and Object.entries() are generally faster and more reliable.