function $(i){

  return document.getElementById(i);

}

function verifVille(that){

  if(that.value.length==0){

      $('erreur_ville').style.display='none';

      that.className='repos';

  }

  else{

    if(isNaN(that.value)){


      that.className='repos';

      if(that.value.length<3){

       $('erreur_ville').style.display='block';

        that.className='erreur';

      }

      else{

        $('erreur_ville').style.display='none';

        that.className='repos';

      }

    }

    else{

      $('erreur_ville').style.display='none';
    }
  }
}

function verifMail(that){

if(that.value.length==0){
	that.className='repos';

    $('erreur_mail').style.display='none';
}else{
	  
   if(validMail(that.value)){

     that.className='repos';

     $('erreur_mail').style.display='none';

   }

  	else{

    	that.className="erreur";

    	$('erreur_mail').style.display='block';
  	}
  }
}

function validMail(mail){

  	var place = mail.indexOf("@",1);

  	var point = mail.indexOf(".",place+1);

  	if ((place > -1)&&(mail.length >2)&&(point > 1)){

  		return true;

  	}

  	else{

  		return false;

  	}

}

function toggle(id){

  var i=$(id);

  if(!i){

    alert(id+" n'existe pas!");

    return false;

  }

  if(i.style.display!="block"){

    i.style.display="block";

  }

  else{

    i.style.display="none";

  }

}