function checkform() {
        var e = false;
        if (document.getElementById("naam").value == "") {
            document.getElementById("naam").className = "error";
            e = true;
        } else {
            document.getElementById("naam").className = "prima";
        }
        if (document.getElementById("email").value == "") {
            document.getElementById("email").className = "error";
            e = true;
        } else {
            document.getElementById("email").className = "prima";
        }
        if (document.getElementById("textbody").value == "") {
            document.getElementById("textbody").className = "error";
            e = true;
        } else {
            document.getElementById("textbody").className = "prima";
        }

    if (e == true) {
        alert("Please enter all fields.");
    } else {
        document.getElementById('contactform').submit();
    }

}