Event.observe(window,'load',function ()
{
  $$('.overlabel').invoke('overlabel');
});

[Edit 20090223: Ajout exemple avec invoke]

Exemple: Lien "Développer / Réduire au titre sur la page" d'accueil.

$$('.snippet').invoke('toggle');

ou itération manuelle:

function toggle_snippets()
{
    var f = $$('.post-content');
    for(var i=0; i < f.length; i++) {
        f[i].toggle();
    }
}

<?php echo javascript_tag("
  function add_bar(text, li)
  {
    var bar_id = li.id;
    $('bar').value = '';
    var ajax_url= '". url_for('@member_add_bar_get'). "?bar_id=' + bar_id;
    new Ajax.Request(ajax_url,
    {
      onSuccess: function(transport)
      {
        $('member_myfavbarsbox_list').update(transport.responseText);
      }
    });
  }
") ?>
 
<?php 
echo input_auto_complete_tag('bar', '',
  array(
    'module' => 'bar',
    'action' => 'autoComplete',
  ),
  array(
    'autocomplete' => 'off', 
    'size'         => '50',
    'indicator'    => 'indicator',
  ),
  array(
    'use_style' => true,
    'frequency' => "0.2, paramName: 'string_start', afterUpdateElement: add_bar, method: 'get'",
  ));
?>

var Fruit = Class.create();
Fruit.prototype = {
  initialize: function(fruit){
    this.fruit = fruit;
  },
  toString: function(){
    return 'I am a fruit and my name is "' + this.fruit + '".'; 
  }
}
var apple = new Fruit('apple');
 
$('fruits').update(apple);
$('fruits').innerHTML;
// -> 'I am a fruit and my name is "apple".'

String.prototype.trim = function()
{
    return this.replace(/(?:^\s+|\s+$)/g, "");
}
 

ou utiliser la fonction prototype

$F('dc_message_to_id').strip();
 

'onchange' =>
                 remote_function(array(
                   'update' => 'item_domain',
                   'url' => 'list/subdomain',
                   'with' => "'id=' + this.options[this.selectedIndex].value"
                 ))