Retrieves the class associated with an object.
Syntax
const JSClass * JS_GetClass(JSObject *obj);
Name | Type | Description |
---|---|---|
cx |
JSContext * |
Any context associated with the runtime in which obj exists. |
obj |
JSObject * |
Object to get the class from. |
In SpiderMonkey versions prior to SpiderMonkey 1.8.8,
JS_GetClass
took both a JSContext*
and a JSObject*
as arguments in thread-safe builds, and in non-thread-safe builds it took only a JSObject*. The JS_GET_CLASS(cx, obj)
macro abstracted away this detail. Newer versions have removed the context argument, so that the same signature is used regardless whether or not the build is thread-safe.Description
JS_GetClass
returns a pointer to the JSClass
associated with a specified JS object, obj
. The application must treat the JSClass
as read-only. If obj
has no JSClass
, this returns NULL
.
To check the type of an object, use JS_HasInstance
instead. For a stricter, exact-match-only check, use JS_InstanceOf
or JS_GetInstancePrivate
.