Código HTML:
<script type="text/javascript">
var req;
function validate() {
var idField = document.getElementById("userID");
var url = "Validador?id=" + escape(idField.value);
if (window.XMLHttpRequest) {
req = new XMLHttpRequest();
} else if (window.ActiveXObject) {
req = new ActiveXObject("Microsoft.XMLHTTP");
}
req.open("GET", url, true);
req.onreadystatechange = callback;
req.send(null);
}
function callback() {
if (req.readyState == 4) {
if (req.status == 200) {
// update the HTML DOM based on whether or not message is valid
parseMessage();
}
}
}
function parseMessage() {
var message = req.responseXML.getElementsByTagName("message")[0];
setMessage(message.childNodes[0].nodeValue);
}
function setMessage(message) {
var userMessageElement = document.getElementById("userIdMessage");
alert(userMessageElement);
userMessageElement.innerHTML = "<font color=\"red\">" + message + " </font>";
}
</script></head>
<body>
<input type="text" name="valor" id="userID" onkeyup="validate()">
</body> Código HTML:
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException {
throws ServletException, IOException {
String targetId = request.getParameter("id");
if ((targetId != null) && !targetId.equals("hola")) {
response.setContentType("text/xml");
response.setHeader("Cache-Control", "no-cache");
response.getWriter().write("<message>invalid</message>");
} else {
response.setContentType("text/xml");
response.setHeader("Cache-Control", "no-cache");
response.getWriter().write("<message>valid</message>");
}
}
)
xq da ese error ???