Find a specified numeric property of an object and return its current value.
Syntax
bool JS_GetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::MutableHandleValue vp);
Name | Type | Description |
---|---|---|
cx |
JSContext * |
The context in which to perform the property lookup. Requires request. In a JS_THREADSAFE build, the caller must be in a request on this JSContext . |
obj |
JS::HandleObject |
The object to search for the element. |
index |
uint32_t |
Index of the element to look up. |
vp |
JS::MutableHandleValue |
Out parameter. On success, *vp receives the current value of the element, if it exists, and undefined otherwise. |
Description
JS_GetElement
examines a specified JS object, obj
, and its prototype chain, for an element or numeric property numbered index
.
If the element exists, JS_GetElement
sets *vp
to the element's current value. If not, it sets *vp
to undefined
and returns true
(to indicate no error occurred). If the search fails with an error or exception, JS_GetElement
returns false
, and the value left in *vp
is undefined.