propertyNames
Return an array of an object's own enumerable and non-enumerable property names.
Usage
var propertyNames = require( '@stdlib/utils/property-names' );
propertyNames( obj )
Returns an array
of an object's own enumerable and non-enumerable property names.
var obj = {
'a': 1,
'b': 2
};
var keys = propertyNames( obj );
// e.g., returns [ 'a', 'b' ]
Notes
- Name order is not guaranteed, as
object
key enumeration is not specified according to the ECMAScript specification. In practice, however, most engines use insertion order to sort anobject
's keys, thus allowing for deterministic extraction. - In contrast to the built-in
Object.getOwnPropertyNames()
, if providednull
orundefined
, the function returns an emptyarray
, rather than throwing an error.
Examples
var defineProperty = require( '@stdlib/utils/define-property' );
var propertyNames = require( '@stdlib/utils/property-names' );
function Foo() {
this.beep = 'boop';
this.a = {
'b': 'c'
};
defineProperty( this, 'baz', {
'value': 'qux',
'configurable': true,
'writable': true,
'enumerable': false
});
return this;
}
Foo.prototype.foo = [ 'bar' ];
var obj = new Foo();
var keys = propertyNames( obj );
console.log( keys );
// e.g., => [ 'beep', 'a', 'baz' ]