Use JavaScript in operator to checks if the object has key. Use myObj.hasOwnProperty('key')
to check an object’s own keys and will only return true
if key
is available on myObj
directly:
if ('key' in myObj)
And the inverse.
if (!('key' in myObj))
Note: The in
operator matches all object keys, including those in the object’s prototype chain.
OR
myObj.hasOwnProperty('key')
Unless you have a specific reason to use the in
operator, using myObj.hasOwnProperty('key')
produces the result most code is looking for.
JavaScript checks if the object has key
Simple example code checking name key in given object.
<!DOCTYPE html>
<html>
<body>
<script>
const item = { id: '101', name: 'Goggles', price: 1499 };
if ('name' in item){
console.log(item)
}
</script>
</body>
</html>
Output:

Another way is to use the hasOwnProperty()
method of the object:
const item = { id: '101', name: 'Goggles', price: 1499 };
var res = item.hasOwnProperty('color')
console.log(res)
Output: false
Do comment if you have any doubts or suggestions on this Js object topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version

Degree in Computer Science and Engineer: App Developer and has multiple Programming languages experience. Enthusiasm for technology & like learning technical.