test-p8-ajax.js

document.querySelector('form.save').addEventListener('submit', () => {
    let data = FormData();
    data.append('substitute', this.querySelector('input[name=substitute]'));
    data.append('substituted', this.querySelector('input[name=substituted]'));
    let xhr = new XmlHttpRequest();
    xhr.open('POST', '{% url "favorite:save" %}');
    xhr.addEventListener('load', () => {
        const answer = JSON.parse(xhr.responseText);
        if (xhr.status == 200) {
            let status = answer.status;
            if (status == 'success') {
                alert('Favori sauvegardé !');
            }
            else {
                alert('Une erreur est survenue');
            }
        }
        else {
            alert('Une erreur est survenue');
        }
    });
    xhr.send(data);
});