Obsolete since JavaScript 1.8.5
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
Warning: JSObjectOps
is not a supported API. Details of the API may change from one release to the next. This documentation should be considered SpiderMonkey internals documentation, not API documentation. See bug 408416 for details.
JSObjectOps.getProperty
, setProperty
, and deleteProperty
are high-level callbacks that implement object property accesses.
Each of these callbacks is responsible for everything involved with an individual property access operation, including: any locking necessary for thread safety; security checks; finding the property, including walking the prototype chain if needed; calling the lower-level JSClass
hooks; calling getters or setters; and actually getting, setting, or deleting the property once it is found.
Contrast JSClass.getProperty
, JSClass.setProperty
, and JSClass.delProperty
, which are hooks called during property accesses and don't have to implement any of that.
Syntax
typedef JSBool (*JSPropertyIdOp)( JSContext *cx, JSObject *obj, jsid id, jsval *vp);
Name | Type | Description |
---|---|---|
cx |
JSContext * |
Pointer to the JS context in which the property access is happening. |
obj |
JSObject * |
The object to be accessed. |
id |
jsid |
The name or index of the property to access. |
vp |
jsval * |
In/out parameter. See the Description section below. |
Description
Get, set, or delete obj[id]
, returning JS_FALSE
on error or exception, JS_TRUE
on success. If getting or setting, the new value is returned in *vp
on success.
If deleting without error, *vp
will be JSVAL_FALSE
if obj[id]
is permanent, and JSVAL_TRUE
if id
named a direct property of obj
that was in fact deleted, or if id
names no direct property of obj
(id
could name a property of a prototype, or no property in obj
or its prototype chain). This reflects the quirky behavior of delete
as specified in ECMA 262-3 §11.4.1 and §8.6.2.5.