Determine whether a JavaScript array has an element in the specified index.
Syntax
bool JS_HasElement(JSContext *cx, JS::HandleObject obj, uint32_t index, bool *foundp);
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. |
foundp |
bool * |
Out parameter. On success, it stores true to *foundp , false otherwise. |
Description
JS_HasElement
examines a specified JS object, obj
, and its prototype chain, for an element or numeric property numbered index
.
If the element exists, JS_HasElement
sets *foundp
to true
. If not, it sets *foundp
to false
and returns true
(to indicate no error occurred). If the search fails with an error or exception, JS_HasElement
returns false
, and the value left in *foundp
is undefined.