// @version  $Revision: 1.2 $  $Date: 2005/03/04 14:57:08 $  $Author: bill $


function isDefined(property) 
{
  return (typeof property != 'undefined');
}
/*
This function can be used to set an image file name in the form xxx_off to xxx_on.
input: fromImage - string

*/
function checkImage(fromImage) 
{
   if (isDefined(document.images)) 
   {
 
      // get all images (including all <input type="image">s)
      // use getElementsByTagName() if supported
      var images = new Array();
      
      if (isDefined(document.getElementsByTagName)) 
      {
         images = document.getElementsByTagName('img');
         var inputs = document.getElementsByTagName('input');
         for (var i = 0; i < inputs.length; i++) 
         {
            if (inputs[i].type == 'image') 
            {
               images[images.length] = inputs[i];
            }
         }
      }
      // otherwise, use document.images and document.forms collections
      // remove if not supporting IE4, Opera 4-5
      else 
      {
         images = document.images;
         inputs = new Array();
         for (var formIndex = 0; formIndex < document.forms.length; formIndex++) 
         {
            for (var elementIndex = 0; elementIndex < document.forms.elements.length; elementIndex++) 
            {
               if (isDefined(document.forms.elements[i].src)) 
               {
                  inputs[inputs.length] = document.forms.elements[i];
               }
            }
         }
      }
      
      // get all images with '_off.' in src value
      for (var i = 0; i < images.length; i++) 
      {
         if (images[i].src.indexOf(fromImage) != -1)
          {
            temp=images[i].src.replace(/_off\./, '_on.');
            images[i].src=temp;
            break;
          }
      } 
   }
}