文字在刷新后消失

When I run the following code, the req.responseText appears quickly in the div #ajax_msg. When the page refreshes (caused by the location.reload), the div #ajax_msg becomes empty.

JAVASCRIPT CODE:

function jsUpdateCart(){
   var parameter_string = '';

   allNodes = document.getElementsByClassName("process");

   for (i = 0; i < allNodes.length; i++) {
       var tempid = allNodes[i].id;
       var temp = new Array;
       temp = tempid.split("_");
       var real_id = temp[2];
       var real_value = allNodes[i].value;
       parameter_string += real_id +':'+real_value+',';
   }

   var params = 'ids=' + parameter_string;
   var ajax = new Ajax.Updater(
           'ajax_msg', '/welcome/ajax_cart',
            {method:'post', parameters:params, onComplete:showMessage}
    );     
}



function showMessage(req){
     $('ajax_msg').innerHTML = req.responseText;
     location.reload(true);
}

Do you have any idea how to fix this problem?

Thanks in advance!

Stijn