function validate() {
    if (document.getElementById("email").value == "") { return (false); }
    if (document.getElementById("subject").value == "") { return (false); }
    if (document.getElementById("message").value == "") { return (false); }
    if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.getElementById("email").value))
    { return (true); }
    else { return (false); }
}

function shwrng() {
    if (document.getElementById("email").value == "") {
        document.getElementById("cne").style.display = "inline";
        document.getElementById("cie").style.display = "none";
    }
    else {
        if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.getElementById("email").value)) {
            document.getElementById("cie").style.display = "none";
            document.getElementById("cne").style.display = "none";
        }
        else {
            document.getElementById("cie").style.display = "inline";
            document.getElementById("cne").style.display = "none";
        }
    }

    if (document.getElementById("subject").value == "")
    { document.getElementById("cns").style.display = "inline"; }
    else
    { document.getElementById("cns").style.display = "none"; }

    if (document.getElementById("message").value == "")
    { document.getElementById("cnm").style.display = "inline"; }
    else
    { document.getElementById("cnm").style.display = "none"; }
}

function send() {
    document.getElementById("load").style.display = "inline";
    if (xmlhttp.readyState == 0 || xmlhttp.readyState == 4) {
        try {
            xmlhttp.open("POST", "cs.php", true);
            xmlhttp.onreadystatechange=function() {
                if (xmlhttp.readyState==4) {
                    document.getElementById("load").style.display = "none";
                    if (document.getElementById("emailform").innerHTML != xmlhttp.responseText) {
                        doInnerHTML("emailform", xmlhttp.responseText);
                    }
                }
            }
            xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
            xmlhttp.send("email=" +
                        document.getElementById("email").value + "&subject=" +
                        document.getElementById("subject").value + "&message=" +
                        document.getElementById("message").value);
        }
        catch(e) {
            doInnerHTML("emailform", e);
        }
    }
}