How to count the number of properties in a JavaScript object
Find out how to calculate how many properties has a JavaScript object
Use the Object.keys()
method, passing the object you want to inspect, to get an array of all the (own) enumerable properties of the object.
Then calculate the length of that array by checking the length
property:
const car = {
color: 'Blue',
brand: 'Ford',
model: 'Fiesta'
}
Object.keys(car).length
I said enumerable properties. This means their internal enumerable flag is set to true, which is the default. Check MDN for more info on this subject.
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