Using AJAX

Yii2 provides appropriate attributes for some widgets to make AJAX calls; sometimes, however, writing a JavaScript code in these attributes will make code hard to read, especially if we are dealing with complex codes.

Consequently, to make an AJAX call, we will use external JavaScript code executed by registerJs().

This is a template of the AJAX class using the GET or POST method:

<?php
$this->registerJs( <<< EOT_JS
     
     // using GET method
$.get({
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

     // using POST method
$.post({
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

EOT_JS
);
?>

An AJAX call is usually the effect of a user interface event (such as a click on a button, a link, and so on). So, most of the time an AJAX call is directly connected to the .on() event of jQuery on the HTML elements (anchors, buttons, and so on). For this reason, it is important to remember how Yii2 renders the name and id...