function trim(stringToTrim) {
    return stringToTrim.replace(/^\s+|\s+$/g, "");
}
function ltrim(stringToTrim) {
    return stringToTrim.replace(/^\s+/, "");
}
function rtrim(stringToTrim) {
    return stringToTrim.replace(/\s+$/, "");
}

function validateEmail(Email) {
    //var emailRegEx = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
    var emailRegEx = /^([a-zA-Z0-9_\.\-\+])+\@(([a-zA-Z0-9\-])+\.)+[a-zA-Z0-9]{2,4}$/;

    str = trim(Email);
    if (str.match(emailRegEx)) {
        return '';
    } else {
        return 'Please enter a valid email address.' + "<br/>";
    }
}