function cancelNavigation() {
    var ret = false;
    var confirmMessage="Tem a certeza que pretende cancelar o seu registo?";
    if(window.confirm(confirmMessage)==true) {
        ret = true;
    }
    return ret;
}

function exitSite() {
    var ret = false;
    var confirmMessage="Tem a certeza que pretende sair?";
    if(window.confirm(confirmMessage)==true) {
        ret = true;
    }
    return ret;
}


/*
 Ocultar/Mostrar Elementos Gráficos
 */
function getBrowserType(){

    var browserType;

    if (document.layers) {
        browserType = "nn4";
    }
    if (document.all) {
        browserType = "ie";
    }
    if (window.navigator.userAgent.toLowerCase().match("gecko")) {
        browserType= "gecko";
    }

    return browserType;
}

function showComponent(element) {

    var browserType = getBrowserType();
    var s =  'document.getElementById("' + element + '")';
    var s2 = 'document.layers["' + element + '"]';
    if (browserType == "gecko" )
        document.poppedLayer =
        eval(s);
    else if (browserType == "ie")
        document.poppedLayer =
        eval(s);
    else
        document.poppedLayer =
        eval(s2);
    //document.poppedLayer.style.visibility = "visible";
    document.poppedLayer.style.display = 'inline';

}


function hideComponent(element) {
    var browserType = getBrowserType();
    var s =  'document.getElementById("' + element + '")';
    var s2 = 'document.layers["' + element + '"]';
    if (browserType == "gecko" )
        document.poppedLayer =
        eval(s);
    else if (browserType == "ie")
        document.poppedLayer =
        eval(s);
    else
        document.poppedLayer =
        eval(s2);
    //document.poppedLayer.style.visibility = "hidden";
    document.poppedLayer.style.display = 'none';
}