var ajaxRequest = null;
  function executeAjaxCommand(page, value) {    
                                                                                       
        abortPendingRequest(ajaxRequest);                            
        ajaxRequest = createAjaxRequest();                                 
        ajaxRequest.onreadystatechange = processResult;                       
        ajaxRequest.open("GET", page + ".aspx" + "?field=" + value + "&rnd=" + Math.random());              
        ajaxRequest.send(null);                              
  }
          
function createAjaxRequest() {
    try {
    return new XMLHttpRequest();
    }
    catch(e) {
      try {
        return new ActiveXObject("Microsoft.XMLHTTP");
      }
      catch(e) {
        alert('cant create Microsoft.XMLHTTP Object');
        return null;        
      }
    }
  }
  
  function abortPendingRequest(request) {   
    if((request != null) && (request.readyState != 0) && (request.readyState != 4)) {
      request.abort();
    }
  }
  
  function processResult(){
    if((ajaxRequest.readyState == 4) && (ajaxRequest.status == 200))  {    }
  }