Prototype Object isArray() Method

Syntax:

Object.isArray(obj);

Return Value :

Returns true if passed object is an array otherwise returns false.

Example:

<html>
<head>
<title>Prototype examples</title>
<script type="text/javascript" 
   src="/javascript/prototype.js">
</script>

<script>

function showResult(){

   var o1 = [1,2,3,4,5];
   var o2 = {name:"prototype", version:1.6};

   alert( "Object.isArray(o1): " + Object.isArray(o1) );
   alert( "Object.isArray(o2): " + Object.isArray(o2) );

}

</script>
</head>

<body>

  <p>Click the button to see the result.</p>
  <br />
  <br />
  <input type="button" value="Result" onclick="showResult();"/>

</body>
</html>

To understand it in better way you can Try it yourself.