The XMLHttpRequest object sends user information to the server asynchronously and receives the corresponding information and data returned by the server. That is, you can request and receive data from the server after the page has been loaded, so that the user experience is better, at the same time, the client and the service XMLHttpRequest object are upgraded to send user information to the server asynchronously and receive the corresponding information and data returned by the server. That is, after the page has been loaded, it can request and receive data from the server. This improves the user experience and increases the interaction speed between the client and the server. AJax is implemented. Therefore, XMLHttpRequest is the most important technology in the Ajax technical system. Without it, other Ajax technologies cannot become an organic whole. Before using the XMLHttpRequest object to send requests and process responses, you must use JavaScript to create the XMLHttpRequestRequest object. Code:
