The static Reflect.defineProperty()
method is like
Object.defineProperty()
but returns a Boolean
.
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Syntax
Reflect.defineProperty(target, propertyKey, attributes)
Parameters
target
- The target object on which to define the property.
propertyKey
- The name of the property to be defined or modified.
attributes
- The attributes for the property being defined or modified.
Return value
A Boolean
indicating whether or not the property was successfully
defined.
Exceptions
Description
The Reflect.defineProperty
method allows precise addition to or
modification of a property on an object. For more details, see the
Object.defineProperty
which is similar.
Examples
Using Reflect.defineProperty()
let obj = {}
Reflect.defineProperty(obj, 'x', {value: 7}) // true
obj.x // 7
Checking if property definition has been successful
With Object.defineProperty
, which returns an object if successful, or
throws a TypeError
otherwise, you would use a
try...catch
block to catch any error that occurred while defining a property.
Because Reflect.defineProperty
returns a Boolean success status, you can
just use an
if...else
block here:
if (Reflect.defineProperty(target, property, attributes)) {
// success
} else {
// failure
}
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Reflect.defineProperty' in that specification. |
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