The Object.defineProperty() method in JavaScript is a Standard built-in object which defines a new property directly on an object or it can also modify the existing property of an object and returns the object.
Syntax:
Object.defineProperty(obj, prop, descriptor)
Parameter: This method accepts three parameters as mentioned above and described below:
- Obj: This parameter holds the Object on which the user is going to define the property.
- Prop: This parameter holds the name of a property that is going to be defined or modified.
- Descriptor: This parameter holds the descriptor for the property being defined or modified.
Return Value: This method returns the object which is passed as the argument to the function.
Below examples illustrate the Object.defineProperty() method in JavaScript:
Example 1: In this example, we will add new properties to an object and print it in the console using the Object.defineProperty() method in JavaScript.
javascript
const geek1 = {}; Object.defineProperty(geek1, 'prop1', { value: 65, writable: false}); geek1.prop1 = 7; console.log(geek1.prop1); const geek2 = {}; Object.defineProperty(geek2, 'prop2', { value: 54, value: 23, value: 12 * 9, }); geek2.prop2; console.log(geek2.prop2); |
Output:
65 108
Example 2: In this example, we will add new properties to an object and print it in the console using the Object.defineProperty() method in JavaScript.
javascript
function gfg() { } let result; Object.defineProperty(gfg.prototype, "valx", { get() { return result; }, set(valx) { result = valx; } }); let vala = new gfg(); let valb = new gfg(); vala.valx = 6; console.log(valb.valx); function gfg1() { } gfg1.prototype.valx = 4; Object.defineProperty(gfg1.prototype, "valy", { writable: false, value: 8 }); let vala = new gfg1(); vala.valx = 4; console.log(vala.valx); console.log(gfg1.prototype.valx); vala.valy = 2; console.log(vala.valy); console.log(gfg1.prototype.valy); |
Output:
6 4 4 8 8
We have a complete list of Javascript Object methods, to check those please go through this JavaScript Object Complete Reference article.
Supported Browsers: The browsers supported by Object.defineProperty() method are listed below:
- Google Chrome
- Firefox
- Opera
- Safari
- Edge
