var comingTime=0;
var leavingTime=0;
var totalTime=0;
var objTime;
var returnvalue;

//used to call at the beginning of an item
function startTimer(){
	//alert("startTimer:comingTime" + comingTime);
	if (comingTime==0){
		objTime = new Date();
		comingTime = objTime.getTime();
	}
	else{
		objTime = new Date();
		leavingTime = objTime.getTime();		
		totalTime = leavingTime - comingTime;		
		if (isNaN(totalTime)){		
			totalTime = 0;
		}
		objTime = new Date();
		comingTime = objTime.getTime();
	}	
}

//used to calculate mastery time of an item
function calculateTimer()
{
	//alert("calculate:totalTime" + totalTime);
	if (totalTime==0){
		objTime = new Date();
		leavingTime = objTime.getTime();	
		totalTime = leavingTime - comingTime;
		if (isNaN(totalTime)){		
			totalTime = 0;
		}
		comingTime = 0;
	}
	//alert(totalTime);
	if (totalTime < 1000) totalTime = 1000;
	returnvalue = totalTime;
	totalTime = 0;	
	return returnvalue;
}
// oVeRLoRDz added function disableKeys July 25 2004
function disableKeys()
{
	var nKeyCode = parseInt(window.event.keyCode);
	var nContextMenuKey = 93, nBackSpaceKey = 8, nLeftArrowKey=37;
	
	//set flag to true will force user jump to the next page
	if (nKeyCode==116)
		blnRefresh=true;
		
	if ( (nKeyCode == nContextMenuKey) || (nKeyCode == nBackSpaceKey) || (nKeyCode == nLeftArrowKey))
		return false;
	else
		return true;
}