Simply using json cannot support cross-domain resource requests. In order to solve this problem, the jsonp data interaction protocol needs to be used. As we all know, the call of js files is not restricted by whether it is cross-domain or not. Therefore, if you want to access data cross-domain through the pure web side, you can only try to encapsulate the json data into a js format file on the remote server for the client to call and Further processing, this is the principle of jsonp protocol.
JSON and JSONP
JSONP is a way to send JSON data without worrying about cross-domain issues. JSONP does not use the XMLHttpRequest object. JSONP uses the
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