/**
 * Checks/unchecks all tables
 *
 * @param   string   the form name
 * @param   boolean  whether to check or to uncheck the element
 *
 * @return  boolean  always true
 */
function setCheckboxes(chkinstance_prefix, myid)
{
	var do_check = (document.getElementById(myid).checked);
	var maxid = document.getElementById(myid).value;
	//:(( vde la d/s cac chkbox phai lien tuc
	for (var i = 1; i <= maxid; i++)
	{
		var instanceid = (chkinstance_prefix+i.toString());
		document.getElementById(instanceid).checked = do_check;
	}
//	var elts = document.forms[the_form].elements[chks_id];
//	if (elts.length) {
  //      for (var i = 0; i < elts.length; i++) {
    //        elts[i].checked = do_check;
      //  } // end for
//    } else {
  //      elts.checked        = do_check;
//    } // end if... else

    return true;
} // end of the 'setCheckboxes()' function

function invertCheckboxesSelect(chkid)
{
	document.getElementById(chkid).checked = (document.getElementById(chkid).checked ? false : true);
}


var http_request = false;
   function makePOSTRequest(url, parameters,st) {
      http_request = false;
      if (window.XMLHttpRequest) { // Mozilla, Safari,...
         http_request = new XMLHttpRequest();
         if (http_request.overrideMimeType) {
         	// set type accordingly to anticipated content type
          
            http_request.overrideMimeType('text/html');
         }
      } else if (window.ActiveXObject) { // IE
         try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
         } catch (e) {
            try {
               http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
         }
      }
      if (!http_request) {
         alert('Cannot create XMLHTTP instance');
         return false;
      }
      
      http_request.onreadystatechange = eval('alertContents'+st);
      http_request.open('POST', url, true);
      http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
      http_request.setRequestHeader("Content-length", parameters.length);
      http_request.setRequestHeader("Connection", "close");
      http_request.send(parameters);
   }