{"json_modified": "2016-03-28T08:13:19.720769", "uuid": "9bf58581-fdf8-4583-975d-dd8a2f491763", "title": "JS_GetArrayLength", "url": "/en-US/docs/Mozilla/Projects/SpiderMonkey/JSAPI_reference/JS_GetArrayLength", "tags": ["SpiderMonkey", "JSAPI Reference"], "translations": [], "modified": "2015-01-05T02:01:33", "label": "JS_GetArrayLength", "localization_tags": [], "locale": "en-US", "id": 14684, "last_edit": "2015-01-05T02:01:23", "summary": "<strong><code>JS_GetArrayLength</code></strong> gets the <code>.length</code> property of <code>obj</code> as though by calling <a href=\"/en-US/docs/Mozilla/Projects/SpiderMonkey/JSAPI_reference/JS_GetProperty\" title=\"JS_GetProperty examines a specified JS object obj and its prototype chain for a property with the specified name. It behaves like the JavaScript expression obj[name]. JS_GetUCProperty is the Unicode version of the function. JS_GetPropertyById is the same but takes a JS::HandleId for the property name.\"><code>JS_GetProperty</code></a> and converts it to a 32-bit unsigned integer. If <code>obj</code> is an array (see <a href=\"/en-US/docs/Mozilla/Projects/SpiderMonkey/JSAPI_reference/JS_IsArrayObject\" title=\"JS_IsArrayObject determines if a specified object, obj or value, is an Array object. If so, JS_IsArrayObject returns true. Otherwise it returns false.\"><code>JS_IsArrayObject</code></a>), this is guaranteed to succeed, because the <code>.length</code> property of an array is always a number and can't be deleted or redefined.", "sections": [{"id": "Quick_Links", "title": null}, {"id": "Syntax", "title": "Syntax"}, {"id": "Description", "title": "Description"}, {"id": "See_Also", "title": "See Also"}], "slug": "Mozilla/Projects/SpiderMonkey/JSAPI_reference/JS_GetArrayLength", "review_tags": []}