function changepage(action){
  req=action.split(',');
  if (action!=undefined){
    if (req[2]==undefined ){
        document.getElementById("action").value = req[1];
        document.forms[req[0]].submit();
    }else{
         if (req[0]!='nombrepage'){
              switch(req[1]){
                case "marque" :
                  document.getElementById("requete").value = 'marque=';
                  document.getElementById("condition").value = req[0];
                  document.getElementById("page").value = '1';
                  break;
                case "prix" :
                      thevalue=document.getElementById("price").value.split('/');
                      switch (thevalue[0]){
                        case '0':
                            document.getElementById("requete").value = "price<=";
                            document.getElementById("condition").value = 500;
                            document.getElementById("page").value = '1';
                            break;
                        case '2000' :
                            document.getElementById("requete").value = "price>=";
                            document.getElementById("condition").value = 2000;
                            document.getElementById("page").value = '1';
                            break;
                        case 'all' :
                            document.getElementById("requete").value = "";
                            document.getElementById("condition").value ='';
                            document.getElementById("page").value = '1';
                            break;
                        default:
                            document.getElementById("requete").value = "price between " + thevalue[0] + " and ";
                            document.getElementById("condition").value = thevalue[1];
                            document.getElementById("page").value = '1';
                            break;
                      }
                      break;
                case "view_page" :
                    document.getElementById("page").value = req[0];
                    break;
                default:
                  if (req[0]!='rien'){
                      document.getElementById("sortby").value = req[0];
                  }
              }
         }
      }

     if (document.getElementById("nombrepage").value!=''){
         document.getElementById("nbpage").value = document.getElementById("nombrepage").value;
         document.getElementById("page").value = '1';
     }
     document.forms[req[2]].submit();
  }

 }
 
 function Verifierheight(){

    var divh = document.getElementById('left_column').offsetHeight;
    var divrighth = document.getElementById('right_column').offsetHeight;
    if (divh <divrighth){
        document.getElementById('left_column').style.height = divrighth + 'px';
    }else{
       document.getElementById('right_column').style.height = divh + 'px';
    }
}