function Calendario() {

    /* ********************************************************************************* */
    /* MOSTRA CALENDARIO */
    this.Abrir = function (Ano, Mes) {
        // AJAX
        // Criar objecto do tipo XMLHttpRequest

        this.Ano = Ano;
        this.Mes = Mes;

        var xmlObj = criarXMLObj();

        xmlObj.open("GET", "/Inc/Calendario.aspx?a=" + this.Ano + "&m=" + this.Mes);
        xmlObj.send(null);

        xmlObj.onreadystatechange = function () {
            if (xmlObj.readyState <= 3) {
                document.getElementById("div_calendario").innerHTML = "<div style='text-align: center;'>"
                                                                   + " <img src='/Imagens/Icons/Load.gif' alt='A carregar calendario...' title='A carregar calendario...'/>"
                                                                   + " A carregar calendario..."
                                                                   + "</div>";
            }


            if (xmlObj.readyState == 4) {
                document.getElementById("div_calendario").innerHTML = xmlObj.responseText;
            }
        }
    }
}