keys method
获取 js 对象的所有 key, 等同于 Object.keys(v)
Implementation
@override
JSFValue keys(JSFContext ctx) {
if (_objectKeys == null) {
final object = ctx.globalObject.getProperty('Object');
_objectKeys = object.getProperty('keys');
assert(_objectKeys!.isFunction());
}
if (_objectKeys != null) {
return _objectKeys!.callAsFunction(arguments: [this]);
}
return JSFValueJSCImpl.makeUndefined(ctx);
}