Prevent the event from being triggered 2 times

Question

When I ask to open a modal for the first time it does the actions correctly, but when I close and open again the modal it performs the function twice, as I avoid this?

function acoesModal(){
    $('div#fixa').css('z-index', '0');
    $('.back-captcha').slideDown(500);
    $('.captcha').fadeIn(500);

    $('body').on('click','.captcha .fechar,.captcha button#retorno',function(event) {
            event.preventDefault();             
            $('div#fixa').removeAttr('style');
            $('.back-captcha').slideUp(500);
            $('.captcha').fadeOut(300);
            $('.captcha form textarea').val('');
        });

Answer 1

There are two ways.

Using the function one.

$('body').one('click', function() {
    console.log('Esta função será executada apenas uma vez');
});

Using the off.

// removo todos os eventos do body com o namespace
// .fecharModal antes de adicioná-los novamente
$('body').off('.fecharModal').on('click.fecharModal', function() {
    console.log('Esta função será executada apenas uma vez');
});

The first way works well in cases where the event will happen only once. The second can be used in cases where the event can occur several times.