Prototype - $A() Method

The $A() function converts the single argument it receives into an Array object.

One suggested use is to convert DOM NodeLists into regular arrays, which can be traversed more efficiently.

Syntax

$A(iterable)

Return Value

List of elements in the form of array.

Example

<html>
   <head>
      <title>Prototype examples</title> 
      <script type = "text/javascript" src = "/javascript/prototype.js"></script>
      
      <script>
         function showOptions() {
            var NodeList = $('employees').getElementsByTagName('option');
            var nodes = $A(NodeList);
            
            nodes.each(function(node) {
               alert(node.nodeName + ': ' + node.innerHTML);
            });
         }
      </script>
   </head>

   <body>
      <select id = "employees" size = "10" >
         <option value = "5">Mohtashim, Mohd</option>
         <option value = "8">Debi, Patnaik</option>
         <option value = "1">Madisetti, Praveen</option>
      </select>
      <br />
      
      <input type = "button" value = "Show the options" onclick = "showOptions();"/>
   </body>
</html>

Output

prototype_utility_methods.htm