JS_GetElement

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.

See Also