Difference between these methods?

Question

Any difference in these three
object.keys()
for in loop
object.getOwropertyNames()

Answer 1

yeah there is one difference i know

object.keys() will return an array of all keys which are enumerable ( means countable or numerable ).

object.getOwnpropertyNames() will return an array of all the key, does not matter if they are enumerable or not . it will return every property.

similarly
for in loop will iterate over only those keys which are enumerable.

for example

var objName = {

prop1: { enumerable: true, value: 100 },

prop2: { enumerable: false, value: 9999 },

prop3: 555 // by default all property enumerable value is set to true

}

then

Object.keys(objName) // [ "prop1", "prop3" ]

Object.getOwnpropertyName(a) // [ "prop1", "prop2", "prop3" ]

for in loop will iterate over "prop1" and "prop3"
only not "prop2"

Answer 2

Ty. You mean by default they all are same if we didnt specify whether its enumerable(which i think most people do)

Answer 3

UMAR FAROOQ

yes👍