object.keys

JavaScript
var person={
    "first_name":"Harry",
    "last_name":"Potter",
    "age":14
};
var personSize = Object.keys(person).length; //gets number of properties (3) var myObj = {no:'u',my:'sql'}
var keys = Object.keys(myObj);//returnes the array ['no','my'];myObject = {
	"key": "value"
}

Object.keys(myObject); // get array of keys// Object Entries returns object as Array of [key,value] Array
const object1 = {
  a: 'somestring',
  b: 42
}
Object.entries(object1) // Array(2) [["a", "something"], ["b", 42]]
  .forEach(([key, value]) => console.log(`${key}: ${value}`))
// "a: somestring"
// "b: 42"const object1 = {
  a: 'somestring',
  b: 42,
  c: false
};

console.log(Object.keys(object1));
// expected output: Array ["a", "b", "c"]Object.keys(whateverYourObjectIsCalled)
Source

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