undefine index error

Question

The below error reflecting on front end.

Array ( 
      [type] => 8 
      [message] => Undefined index: price 
      [file] => /home/studious/public_html/maal-php/app/design/frontend/rwd/default/template/catalog/product/brand.phtml [line] => 71 
      )

and am using below code on line 71

<?php
    if($_GET['price']!="")
    {
    $price=str_replace(",", "%2C", $_GET['price']);
 $url="?brands=".$optionId."&price=".$price; 
    }
    else
    {
    $url="?brands=".$optionId;
    $price="";
    }
    ?>

Answer 1

replace if($_GET['price']!="") with

if(isset($_GET['price']) && $_GET['price']!="")