Name
Object.keys() — return own enumerable property names
Availability
ECMAScript 5
Synopsis
Object
.
keys
(
o
)
Arguments
o
An object
Returns
An array that contains the names of all enumerable own
(non-inherited) properties of o
.
Description
Object.keys()
returns an
array of property names for the object o
.
The array only includes the names of properties that are enumerable
and are defined directly on o
: inherited
properties are not included. (See Object.getOwnPropertyNames()
for a way to
obtain the names of non-enumerable properties.) Property names
appear in the returned array in the same order they would be
enumerated by a for/in
loop.
Note that this is not a method to be invoked on an object: it is a global function and you must pass an object to it.
Example
Object
.
keys
({
x
:
1
,
y
:
2
})
// => ["x", "y"]
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