[HTML][AJAX] Problem z formularzem Opcje

[kropla]

Witajcie

Próbuję zrobić formularz który będzie przesyłał dane wykorzystując ajax-a. Trochę poczytałem i znalazłem stronę:

http://www.captain.at/howto-ajax-form-post-get.php

problem mam taki że jak skopiuję sobie kod do swojego pliku to dostaję komunikat There was a problem with the request.

poniżej zawartosc pliku

[HTML] pobierz, plaintext 
<script type="text/javascript" language="javascript">
   var http_request = false;
   function makeRequest(url, parameters) {
      http_request = false;
      if (window.XMLHttpRequest) { // Mozilla, Safari,...
         http_request = new XMLHttpRequest();
         if (http_request.overrideMimeType) {
         	// set type accordingly to anticipated content type
            //http_request.overrideMimeType('text/xml');
            http_request.overrideMimeType('text/html');
         }
      } else if (window.ActiveXObject) { // IE
         try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
         } catch (e) {
            try {
               http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
         }
      }
      if (!http_request) {
         alert('Cannot create XMLHTTP instance');
         return false;
      }
      http_request.onreadystatechange = alertContents;
      http_request.open('GET', url + parameters, true);
      http_request.send(null);
   }
 
   function alertContents() {
      if (http_request.readyState == 4) {
         if (http_request.status == 200) {
            //alert(http_request.responseText);
            result = http_request.responseText;
            document.getElementById('myspan').innerHTML = result;            
         } else {
            alert('There was a problem with the request.');
         }
      }
   }
 
   function get(obj) {
      var getstr = "?";
      for (i=0; i<obj.childNodes.length; i++) {
         if (obj.childNodes[i].tagName == "INPUT") {
            if (obj.childNodes[i].type == "text") {
               getstr += obj.childNodes[i].name + "=" + obj.childNodes[i].value + "&";
            }
            if (obj.childNodes[i].type == "checkbox") {
               if (obj.childNodes[i].checked) {
                  getstr += obj.childNodes[i].name + "=" + obj.childNodes[i].value + "&";
               } else {
                  getstr += obj.childNodes[i].name + "=&";
               }
            }
            if (obj.childNodes[i].type == "radio") {
               if (obj.childNodes[i].checked) {
                  getstr += obj.childNodes[i].name + "=" + obj.childNodes[i].value + "&";
               }
            }
         }   
         if (obj.childNodes[i].tagName == "SELECT") {
            var sel = obj.childNodes[i];
            getstr += sel.name + "=" + sel.options[sel.selectedIndex].value + "&";
         }
 
      }
      makeRequest('get.php', getstr);
   }
</script>
 
 
<input type="button" name="button" value="GET test.html" 
   onclick="javascript:makeRequest('test.html', '');">
<br><br>
<input type="button" name="button" value="GET get.php?test=2" 
   onclick="javascript:makeRequest('get.php', '?test=2');">
<br><br>
 
 
<form action="javascript:get(document.getElementById('myform'));" name="myform" id="myform">
<input type="text" name="myfield" value="teststring"><br>
<input type="radio" name="myradio" value="0" checked> 0
<input type="radio" name="myradio" value="1"> 1<br>
<input type="checkbox" name="mycheck1" value="1"> 1
<input type="checkbox" name="mycheck2" value="2"> 2
<input type="checkbox" name="mycheck3" value="3"> 3
<input type="checkbox" name="mycheck4" value="4"> 4
<input type="checkbox" name="mycheck5" value="5"> 5
<br>
<select name="myselect">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
<br>
<input type="button" name="button" value="Submit" 
   onclick="javascript:get(this.parentNode);">
<input type="submit" name="button" value="Normal Submit Button">
</form>
 
<br><br>
Server-Response:<br>
<span name="myspan" id="myspan"></span>
[HTML] pobierz, plaintext 

w konsoli błędów jest napisane:

Ostrzeżenie: reference to undefined property obj.childNodes[i].tagName

mogę liczyć na pomoc ?

[hiszpanespaniol]

może to i banalne, ale nie może wysłać żądania. czy na pewno testujesz to na serwerze? z parserem php i w ogóle. może w tym problem? kod na stronie do której podałeś link jest identyczny więc powinien działać.