AJAX

To add AJAX functionality to MV, we recommend following these rules:

1. If the project is deployed in a subdirectory, add the path from the root to the project to JavaScript.
2. Create a route with a readable and understandable URL.
3. In the template to which the URL will come, use the methods of the Http class.

Pass the full path to the project to JavaScript in the views/main-header.php file, add a line with the path.

<script type="text/javascript"> const rootPath = '<? echo $mv -> root_path; ?>'; </script>

Add a route and create the required template file to which the AJAX request will go.

//config/routes.php file

'/ajax/form/feedback' => 'ajax/feedback-form.php'

In the JavaScript file, add the code for sending an AJAX request, for example, to JQuery.

$.ajax(
{
    type: 'POST',
    dataType: 'json',
    url: rootPath + 'ajax/form/feedback',
    data: $('#feedback-form').serialize(),
    success: function(data)
    {
        //Response processing (for form)
        if(data.valid)
        {
            ...
        }
        else
        {
            //Array form errors
            data.errors.fields
            
            //Single html with form errors
            data.errors.all
        }
    }
});

In the template file, we check the request and prepare a response in JSON or HTML form if we are generating a fragment of HTML code to insert into the page.

//File views/ajax/feedback-form.php

//First, we check that a POST AJAX request has arrived, if not, then exit
Http::isAjaxRequest('post', true);

//Check for parameters in the request, generate HTML
if(isset($_POST['param']))
{
    $html = $mv -> model -> method();
    
    ...
}

//Or, for example, we process the form
$form -> submit() -> validate();

//At the very end, we return the response in JSON format
$json = ['success' => true];
Http::responseJson($json);

//Other response formats
Http::responseXml($xml);
Http::responseHtml($html);
Http::responseText($text);

If a form is processed in an AJAX request, it is recommended to return a JSON object with the result of the form's getState() method as a response.

//File views/ajax/feedback-form.php

Http::isAjaxRequest('post', true);

$form = new Form('Feedback');
$form -> useAjaxTokenCSRF() -> useJqueryToken();
$form -> submit() -> validate();

if($form -> isValid())
{
    ...
}

Http::responseJson($form -> getState());

If additional data needs to be added to the form state in the response, the addStateValue() method is used.

//File views/ajax/feedback-form.php

if($form -> isValid())
{
    ...

    $form -> addStateValue('link', 'https://...');
}

Http::responseJson($form -> getState());