Tab and Tab+Shift focus on selected div

$(document).ready(function() {

lastIndex = 0;
     $(document).keydown(function(e){
        if(e.keyCode==9)
        var thisTab = $(":focus").attr("tabindex");
if(e.keyCode == 9) {
if(e.shiftKey) {
  //Focus previous input
  if(thisTab == startIndex){
$("#"+tabLimitInID).find('[tabindex='+lastIndex+']').focus();
        return false;
        }

}else {
 if(thisTab == lastIndex){
$("#"+tabLimitInID).find('[tabindex='+startIndex+']').focus();
        return false;
        }
}
}

     });      


 var  setTabindexLimit = function(x,fancyID){
console.log(x);
     startIndex = 1;
lastIndex = x;
tabLimitInID = fancyID;
$("#"+tabLimitInID).find('[tabindex='+startIndex+']').focus();
  }

setTabindexLimit(10,"DivWithTabIndex");


});