The static Reflect.getOwnPropertyDescriptor() method is similar to Object.getOwnPropertyDescriptor(). It returns a property descriptor of the given property if it exists on the object, undefined otherwise.
Syntax
Reflect.getOwnPropertyDescriptor(target, propertyKey)
Parameters
target- The target object in which to look for the property.
propertyKey- The name of the property to get an own property descriptor for.
Return value
A property descriptor object if the property exists in the given target object; otherwise, undefined.
Exceptions
A TypeError, if target is not an Object.
Description
The Reflect.getOwnPropertyDescriptor method returns a property descriptor of the given property if it exists on the object, undefined otherwise. The only difference to Object.getOwnPropertyDescriptor() is how non-object targets are handled.
Examples
Using Reflect.getOwnPropertyDescriptor()
Reflect.getOwnPropertyDescriptor({x: 'hello'}, 'x');
// {value: "hello", writable: true, enumerable: true, configurable: true}
Reflect.getOwnPropertyDescriptor({x: 'hello'}, 'y');
// undefined
Reflect.getOwnPropertyDescriptor([], 'length');
// {value: 0, writable: true, enumerable: false, configurable: false}
Difference to Object.getOwnPropertyDescriptor()
If the first argument to this method is not an object (a primitive), then it will cause a TypeError. With Object.getOwnPropertyDescriptor, a non-object first argument will be coerced to an object at first.
Reflect.getOwnPropertyDescriptor('foo', 0);
// TypeError: "foo" is not non-null object
Object.getOwnPropertyDescriptor('foo', 0);
// { value: "f", writable: false, enumerable: true, configurable: false }
Specifications
| Specification | Status | Comment |
|---|---|---|
| ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Reflect.getOwnPropertyDescriptor' in that specification. |
Standard | Initial definition. |
| ECMAScript Latest Draft (ECMA-262) The definition of 'Reflect.getOwnPropertyDescriptor' in that specification. |
Draft |
Browser compatibility
| Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 49 | (Yes) | 42 (42) | No support | No support | 10 |
| Feature | Android | Chrome for Android | Edge | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic support | No support | 49 | (Yes) | 42.0 (42) | No support | No support | 10 |