// Section 0 (demographics)
function Home(){
    var ret = true;
    if (document.getElementById(prefix + "txtEmail").value == '') {
        document.getElementById("valEmail").style.visibility = 'visible';
        ret = false;
    } else {
        // check the validity of the email address
        var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
        if (reg.test(document.getElementById(prefix + "txtEmail").value) == false) {
            document.getElementById("valEmail").style.visibility = 'visible';
            alert('Invalid email address');
            ret = false;
        } else {
            document.getElementById("valEmail").style.visibility = 'hidden';
        }
    }
    if (document.getElementById(prefix + "txtPassword").value == '') {
        document.getElementById("valPassword").style.visibility = 'visible';
        ret = false;
    } else {
        // check the validity of the email address
        var reg = /^([A-Za-z0-9_\-\.\+\=\?\!\@\#\$\%\^\&\*\(\)]{6,150})$/;
        if (reg.test(document.getElementById(prefix + "txtPassword").value) == false) {
            document.getElementById("valEmail").style.visibility = 'visible';
            alert('Invalid password');
            ret = false;
        } else {
            document.getElementById("valPassword").style.visibility = 'hidden';
        }
    }
    if (document.getElementById(prefix + "txtConfirmPassword").value == '') {
        document.getElementById("valConfirmPassword").style.visibility = 'visible';
        ret = false;
    } else {
        if (document.getElementById(prefix + "txtPassword").value != document.getElementById(prefix + "txtConfirmPassword").value) {
            document.getElementById("valConfirmPassword").style.visibility = 'visible';
            alert('Password confirmation does not match');
            ret = false;
        } else {
            document.getElementById("valConfirmPassword").style.visibility = 'hidden';
        }
    }
    if (document.getElementById(prefix + "ddCountry").selectedIndex == 0)
    {
        document.getElementById("valCountry").style.visibility = 'visible';
       ret = false;
    }else{
        document.getElementById("valCountry").style.visibility = 'hidden';
    }
    if (document.getElementById(prefix + "ddTitle").selectedIndex == 0) {
        document.getElementById("valTitle").style.visibility = 'visible';
        ret = false;
    } else {
        document.getElementById("valTitle").style.visibility = 'hidden';
    }
    if (document.getElementById(prefix + "txtFirstname").value == '')
    {
        document.getElementById("valFirstname").style.visibility = 'visible';
       ret = false;
    }else{
        document.getElementById("valFirstname").style.visibility = 'hidden';
    }
    if (document.getElementById(prefix + "txtLastname").value == '')
    {
        document.getElementById("valLastname").style.visibility = 'visible';
       ret = false;
    }else{
        document.getElementById("valLastname").style.visibility = 'hidden';
    }
    if (!(document.getElementById(prefix + "chkTerms").checked)) {
        alert("You need to agree to the Terms and Conditions before you can join.");
        ret = false;
    }
    if (!ret) {
        alert('Please ensure that all compulsory questions are completed.');
    }
    return ret;
}