How Can I Efficiently Iterate Over JavaScript Objects, Including Handling Inheritance and Chunking?

Iterating Over JavaScript Objects in Parts

Iterating over JavaScript objects requires different approaches compared to iterating over arrays. This is because objects do not have a fixed order like arrays.

Using for .. in

To iterate over the keys (property names) of an object, use the for .. in syntax:

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

Using Object.entries (ES6)

For ES6 and later, Object.entries() returns an array of key-value pairs.

for (let [key, value] of Object.entries(object)) {
  console.log(key, value);
}

Avoiding Inherited Properties

If your object may inherit properties from its prototype, use hasOwnProperty() to exclude them:

for (let key in object) {
  if (object.hasOwnProperty(key)) {
    console.log(key, object[key]);
  }
}

Iterating in Chunks

To iterate over properties in chunks, convert the object keys into an array:

let keys = Object.keys(object);
for (let i = 300; i < keys.length && i < 600; i++) {
  console.log(keys[i], object[keys[i]]);
}

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