JavaScript hasOwnProperty() Method
The “hasOwnProperty()” method in JavaScript is handy for checking if an object has a specific property that belongs to it directly, rather than inherited from its prototype chain. It’s a useful tool for ensuring whether an object possesses its own properties.
Syntax:
object.hasOwnProperty( prop );
Parameters:
- prop: It holds the name in the form of a String or a Symbol of the property to test.
Return Value:
It returns a Boolean value indicating whether the object has the given property as its own property.
Example 1: This example checks the properties of an object.
function checkProperty() {
let exampleObj = {};
exampleObj.height = 100;
exampleObj.width = 100;
// Checking for existing property
result1 = exampleObj.hasOwnProperty("height");
// Checking for non-existing property
result2 = exampleObj.hasOwnProperty("breadth");
console.log(result1);
console.log(result2);
}
checkProperty()
Output
true false
Example 2: This example checks the properties of an object of a class.
function checkProperty() {
function Car(a, b) {
this.model = a;
this.name = b;
}
let car1 = new Car("Mazda", "Laputa");
// Checking for existing property
result1 = car1.hasOwnProperty("model");
// Checking for non-existing property
result2 = car1.hasOwnProperty("wheels");
console.log(result1);
console.log(result2);
}
checkProperty()
Output
true false
We have a complete list of Object methods, and properties to check those please go through this JavaScript Object Complete Reference article.
Supported Browsers:
- Google Chrome 1 and above
- Firefox 1 and above
- Internet Explorer 5.5 and above
- Edge 12 and above
- Safari 3 and above
- Opera 5 and above