Use JavaScript Object hasOwnProperty() method to check if the object has the given property as its own property. This returns true
if the specified property is a direct property of the object — even if the value is null
or undefined
.
And it returns false
if the property is inherited or has not been declared at all.
hasOwnProperty(prop)
Note:Object.hasOwn()
is recommended over hasOwnProperty()
, in browsers where it is supported.
JavaScript hasOwnProperty method
Simple example code.
<!DOCTYPE html>
<html>
<body>
<script>
var x = {
'key': 1
};
if ( x.hasOwnProperty('key') ) {
console.log('has key property');
}
</script>
</body>
</html>
Output:

More Examples
var x = {
y: 10
};
console.log(x.hasOwnProperty("y")); //true
console.log(x.hasOwnProperty("z")); //false
const object1 = {};
object1.property1 = 42;
console.log(object1.hasOwnProperty('property1'));
// expected output: true
Do comment if you have any doubts or suggestions on this JS method code.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version

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