This feature is deprecated in favor of defining getters using the object
initializer syntax or the Object.defineProperty() API. While this
feature is widely implemented, it is only described in the ECMAScript
specification because of legacy usage. This method should not be used since
better alternatives exist.
The __defineGetter__ method binds an object's property to
a function to be called when that property is looked up.
Syntax
obj.__defineGetter__(prop, func)Parameters
prop- A string containing the name of the property to bind to the given function.
func- A function to be bound to a lookup of the specified property.
Return value
Description
The __defineGetter__ allows a getter
to be defined on a pre-existing object.
Examples
Non-standard and deprecated way
var o = {};
o.__defineGetter__('gimmeFive', function() { return 5; });
console.log(o.gimmeFive); // 5
Standard-compliant ways
// Using the get operator
var o = { get gimmeFive() { return 5; } };
console.log(o.gimmeFive); // 5
// Using Object.defineProperty
var o = {};
Object.defineProperty(o, 'gimmeFive', {
get: function() {
return 5;
}
});
console.log(o.gimmeFive); // 5
Specifications
| Specification |
|---|
| ECMAScript (ECMA-262) The definition of 'Object.prototype.__defineGetter__()' in that specification. |
Browser compatibility
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