/*************************************************************************************************/

function validateString(field, len, msg) {
    if (field.value.length < len || field.value == null || /^\s+$/.test(field.value)) {
        alert(msg);
        field.focus();
        return false;
    }

    return true;
}

/*************************************************************************************************/

function validateEmail(field, msg, allowNull) {
    if (field == undefined) { alert('Sorry, an error occured. Please try refreshing your browser'); }
    if (allowNull == undefined) { allowNull = 'NO'; }
    if (msg == '' || msg == undefined) { msg = 'Invalid email address. Please check it'; }

    if (allowNull == 'NO') {
        if (field.value.length < 1) {
            field.focus();
            alert('Please type the email address');
            return false;
        }
        var regex = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
        var address = field.value;
        if (regex.test(address) == false) {
            field.focus();
            alert(msg);
            return false;
        } else {
            return true;
        }
    }
}

/*************************************************************************************************/

function validateNumbers(field) {

    var valid = "0123456789"
    var ok = true;
    var temp;
    for (var i = 0; i < field.value.length; i++) {
        temp = "" + field.value.substring(i, i + 1);
        if (valid.indexOf(temp) == "-1") ok = false;
    }
    if (ok == false) {
        field.focus();
        field.select();
        return false;
    }
    else { return true; }
}