Why does the post request of ajax trigger options first?
what should I do if I want to trigger the options request first and then the post request?
Why does the post request of ajax trigger options first?
what should I do if I want to trigger the options request first and then the post request?
A CORS (cross-domain) request that is not a simple request adds a HTTP query request, called a "pre-check" request (preflight), before the formal communication.
that is, an post request will be sent before your OPTIONS request
take a look at this: Cross-domain Resource sharing CORS
because your requestoriginating domainandarriving domainare not in the samedomain, the browser will first launch aOPTIONSrequest to askarriving domainto allow thoserequest methods,request header,initiating domain, etc.
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