$(document).ready(function() {

    // Event listener for submit button on mail magazine form
    $('#mail_magazine_form').submit(function(){
        return mailMagValidation();
    });

});

// Form validation for mail magazine form
function mailMagValidation(){
    result = false;

    if ($('#mail_magazine_email').val() == '') {
        alert('メールアドレスを入力してください');
    } else {
        result = true;
    }

    return result;
}