Getting back a response code other than HTTP 200 doesn't guarantee that the server didn't successfully deliver the message.

获取一个并非HTTP 200的响应并不能保证服务器没有成功的传递消息。

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If the user is authorized to access the resource, the response is an HTTP 200 response, and the requested resource is served.

如果用户被授权访问资源，所得到的响应是HTTP 200响应，将提供所请求的资源。

youdao

If the call is successful (returning an HTTP 200), the update function is called. Listing 15 USES Prototype for the Ajax call.

如果调用成功(返回HTTP 200)，则会调用update函数。

youdao