Sometimes, we want to get all keys of a deep object in JavaScript.
In this article, we’ll look at how to get all keys of a deep object in JavaScript.
How to get all keys of a deep object in JavaScript?
To get all keys of a deep object in JavaScript, we can recursive traverse the object to get the keys.
For instance, we write:
const obj = {
foo: 'bar',
count: '3',
counter: {
count: '3',
},
baz: {
test: "qux",
tester: {
name: "Ross"
}
}
};
const objectDeepKeys = (obj, keys = []) => {
for (const key of Object.keys(obj)) {
keys.push(key)
if (typeof obj[key] === 'object' && obj[key] !== null) {
objectDeepKeys(obj[key], keys)
}
}
return keys
}
console.log(objectDeepKeys(obj))
to define the objectDeepKeys function that takes the obj object to traverse and the array of keys.
In the function, we loop through each key we get from Object.keys with a for-of loop.
And in the loop, we have keys.push(key) to append the key to keys.
If obj[key] is an object and it’s not null, we call objectDeepKeys to do the same thing in the next level.
As a result, we see ['foo', 'count', 'counter', 'count', 'baz', 'test', 'tester', 'name'] logged.
Conclusion
To get all keys of a deep object in JavaScript, we can recursive traverse the object to get the keys.
