AJAX in Javascript

AJAX in Javascript AJAX (Asynchronous JavaScript and XML) is a programming technique that allows you to update content on a web page without having to completely reload it. This is possible thanks to the use of asynchronous requests in Javascript, which make it possible to communicate with the server without interrupting the execution of the code. AJAX is widely used in modern web applications, as it allows for a more fluid and faster experience for the user, avoiding the need to reload the page with each interaction. In addition, it allows you to update content dynamically, without having to load the entire page again. To use AJAX in Javascript, it is necessary to create an asynchronous request using the XMLHttpRequest object. This object allows communication with the server and manipulation of received data. The code below shows an example of how to create an AJAX request in Javascript: ```javascript var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { // Handle incoming data here } }; xhttp.open("GET", "server_url", true); xhttp.send(); ``` In the code above, an XMLHttpRequest object is created and a callback is defined to be executed when the request is completed. Within this callback, it is possible to manipulate the data received from the server. The open method is used to define the request type and the server URL, while the send method is used to send the request. In addition, it is possible to use libraries such as jQuery to facilitate the creation of AJAX requests in Javascript. The code below shows an example of how to use jQuery to create an AJAX request: ```javascript $.ajax({ url: "server_url", method: "GET", success: function(data) { // Handle incoming data here } }); ``` In the code above, jQuery's ajax method is used to create a GET request for the server's URL. The success callback is executed when the request is successfully completed, allowing manipulation of the received data. In short, AJAX in Javascript is a very useful technique for developing modern web applications, allowing content to be updated dynamically and without the need to completely reload the page. With the use of libraries such as jQuery, it is possible to facilitate the creation of AJAX requests in Javascript, making the process simpler and more efficient.

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