var m_req = ["name","email","message"];
var m_email = "email"; 

function m_trim(str) { return str.replace(/^\s\s*/, '').replace(/\s\s*$/, ''); }
function m_val() {
    var stop = false;
    for (var i=0; i < m_req.length; i++) {
        if (m_trim(document.forms[0].elements[m_req[i]].value) == "") {
            alert("Fill in the required fields *.");
            var stop = true;
            break;
        }
    };

    if (!stop) {
        var emailFilter = /^([a-zA-Z0-9])+([a-zA-Z0-9\._-])*@([a-zA-Z0-9_-])+([a-zA-Z0-9\._-]+)+$/; // regex matches the regex in the php.
        if (!(emailFilter.test(m_trim(document.forms[0].elements[m_email].value)))) { 
            alert("Enter a valid email address.");
            var stop = true;
        }
    }
    if (stop) return false;
    else return true;
}