Checking if a key exists in a JavaScript object?

Question

How do I check if a particular key exists in a JavaScript object or array?

If a key doesn\'t exist, and I try to access it, will it return false? Or throw an error?<

Answer 1

vanila js

yourObjName.hasOwnProperty(key) : true ? false;

If you want to check if the object has at least one property in es2015

Object.keys(yourObjName).length : true ? false