The reason why HTTP status codes are different is to more accurately represent the server's processing results and status of the request. Different status codes provide different information, allowing the client to understand the server's handling of the request and take appropriate measures.
The following are some common situations that result in different HTTP status codes:
Request success and failure: The first number of the status code represents the type of response . The 2xx series of status codes indicate success, such as 200, which indicates that the request was successful, while the 4xx and 5xx series of status codes indicate that the request failed, indicating client errors and server errors respectively.
Requested resource status: Different status codes can reflect whether the requested resource exists, whether it has been moved or redirected, and whether permissions or access restrictions have been encountered. For example, 404 means that the requested resource does not exist, 301 means that the resource has been permanently moved to a new URL, 403 means access is forbidden, etc.
Redirect: The 3xx series of status codes are used for redirection. Different 3xx status codes represent different types of redirection, such as 302 temporary redirection, 301 permanent redirection, 307 temporary redirection but requiring the client to keep the request method unchanged, etc.
Security and authentication: Certain status codes are used to indicate situations related to security and authentication, such as 401 indicating that authentication is required, 403 indicating that access is prohibited, and 407 indicating that proxy identity is required Verification etc.
By using different status codes, the HTTP protocol can provide more precise information and guidance, helping clients and developers understand the processing results of requests and take corresponding actions based on different status codes. processing measures to optimize the interactive experience and error handling mechanism of web applications.