Method PUT is not allowed by Access-Control-Allow-Methods. Method DELETE is not allowed by Access-Control-Allow-Methods. 当然,我可以修改我的响应头包括这两个方法来解决这个问题。 但是我希望理解这些与ExpressJS基于绑定到路由的自动添加的基本“允许”之间的区别。 有什么不同?