Highlight first field on page load, enter sends submit request, double quote to single quote. Submission focuses first field again

examples/jqueryexample/templates/index.html

@@ -2,20 +2,32 @@
 {% block body %}
 <script type=text/javascript>
   $(function() {
-    $('a#calculate').bind('click', function() {
+    var submit_form = function(e) {
       $.getJSON($SCRIPT_ROOT + '/_add_numbers', {
         a: $('input[name="a"]').val(),
         b: $('input[name="b"]').val()
       }, function(data) {
-        $("#result").text(data.result);
+        $('#result').text(data.result);
+        $('input[name=a]').focus().select();
       });
       return false;
+    };
+
+    $('a#calculate').bind('click', submit_form);
+
+    $('input[type=text]').bind('keydown', function(e) {
+      if (e.keyCode == 13) {
+        submit_form(e);
+      }
     });
+
+    $('input[name=a]').focus();
   });
 </script>
 <h1>jQuery Example</h1>
-<p><input type=text size=5 name=a> +
-   <input type=text size=5 name=b> =
-   <span id=result>?</span>
+<p>
+  <input type=text size=5 name=a> +
+  <input type=text size=5 name=b> =
+  <span id=result>?</span>
 <p><a href=# id=calculate>calculate server side</a>
 {% endblock %}