topical media & game development
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

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professional-ria-04-HelloWorldv2.htm / htm



  <!--
  Second version of HelloWorld.html
     
  This version adds:
    - javascript function - handleCountryChange() - called when
      select is modified. Creates an asynchronous call.
    - javascript function - helloCallback() - callback invoked after
      the request is handled. Initial implementation just displays an alert.
  -->
  <html>
    <head>
      <script type="text/javascript">
        var xmlRequest = new XMLHttpRequest();
  
        function handleCountryChange() {
          var countryValue = document.getElementById("country").value;
          var uri = "helloFiles/" + countryValue + ".txt";
          xmlRequest.open("GET", uri, true);
          xmlRequest.onreadystatechange = helloCallback;
          xmlRequest.send(null);
        }
  
        function helloCallback() {
          if (xmlRequest.readyState == 4) {
            alert("Hello callback was invoked!");
          }
        }
      </script>
    </head>
    <body>
      <form id="helloForm"><label>Say Hello: </label>
        <select id="country" onkeyup="handleCountryChange()"
         onchange="handleCountryChange()">
          <option>France</option>
          <option>Germany</option>
          <option>Spain</option>
          <option>USA</option>
        </select>
      </form>
      <p/>
        <label id="messageLabel" style="border: thin solid"></label>
    </body>
  </html>
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

(C) Æliens 20/2/2008

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