1 app.all('*', function (req, res, next) {
 2     res.header('Access-Control-Allow-Origin', '*');
 3     res.header('Access-Control-Allow-Headers', 'Content-Type, Content-Length, Authorization, Accept, X-Requested-With , yourHeaderFeild');
 4     res.header('Access-Control-Allow-Methods', 'PUT, POST, GET, DELETE, OPTIONS');
 5     if (req.method == 'OPTIONS') {
 6         res.send(200);
 7     } else {
 8         next();
10 });