如何在不影响搜索数据的情况下在同一页面中设置和销毁cookie？

Question

I am trying to search data and display data in same page with help of cookies.it is work fine but when i try to destroy cookies,the result data is loss and no searching happen.i also use pagination. when i click on another page no. in pagination,same the result data is lost.this is only happen when i destroy the cookies. and if i not destroy the cookies the data is continue display even i press enter in url.
php code:

   $depart_type=''; 
   if(isset($_COOKIE['depart_type']))
      {
        $depart_type = $_COOKIE['depart_type'];
      }   
    if($_POST['department_type']!='')
      {
        $depart_type = $_POST['department_type'];
        setcookie("depart_type",$depart_type,time()+3600,"/"); 
     }       
     $whr ="1";
    if($depart_type!="")
    {
        $whr .= "  AND `department_type` = '$depart_type'";
     } 
       $QryStaff = mysql_query("select * from `tbl_staff` where $whr) or die(mysql_error());    

so, problem is when and where i destroy or unset cookies?

Answer 1

I have a suggestion. You should make one button. And on the click event of that button, clear the cookies. Not a professional solution, though it will definitely work..

Hope it helps.