Common Status Codes

[200]

RequestSucceeded, The request's desired response header or data body will be returned with this response.
[301]

requested resource permanently moved to a new location , in addition, any reference to this resource in the future should use one of the Uris returned by this response. If possible, clients with the link editing function should automatically change the requested address to the address returned from the server. This response can be cached unless otherwise specified.
the new URI must be in returned in the location field. Unless this is a head request, otherwise, the response entity should contain hyperlinks and short descriptions pointing to the new URI .
If This Is Not A Get or head request, therefore, the browser prohibits automatic redirection unless confirmed by the user because the request conditions may change. Note: For Some browsers that use the HTTP/1.0 protocol, when the post request sent by them receives a response from 301 , the next redirect request will be changed to the Get method.
[302]

The requested resources are now temporary from differentUriResponse Request. Because of thisRedirection is temporaryThe client should continue to send requests to the original address. OnlyCache-controlOrExpiresIf the response is specified, the response can be cached. New temporaryUriThe responseLocationReturned in the domain. Unless this isHeadRequest. Otherwise, the response entity should containUri.
[403]

The server has understood the request but refused to execute it. . Unlike 401 , identity authentication does not provide any help, and this request should not be submitted repeatedly. If this is not a head request, and the server wants to know why the request cannot be executed, the reason for rejection should be described in the entity. Of course, the server can also return a 404 response, if it does not want the client to obtain any information.
[404]
request failed, the requested resource is not found on the server . No information can tell the user whether the situation is temporary or permanent. If the server knows the situation, you should use the 410 Status Code to inform the old resource of some internal configuration mechanism problems, it is permanently unavailable and there is no jump address. 404 this status code is widely used when the server does not want to reveal why the request is rejected or no suitable response is available..
[500]
the server encountered an unexpected situation, which made it unable to process the request. Generally, this problem occurs in the Program code error appears.