function setQuantity(pcID, pnOperation, pnMin, pnMax)
{
var lnCurrentQuantity = parseInt(document.getElementById(pcID).value);
var lnNewQuantity = lnCurrentQuantity;

switch(pnOperation)
	{
	case 1: // increase quantity by 1
	lnNewQuantity++;
		if(lnNewQuantity > pnMax)
		{
		lnNewQuantity = lnCurrentQuantity;
		}
	break;
	case 2:// decrease quantity by 1
	lnNewQuantity--;
		if(lnNewQuantity < pnMin)
		{
		lnNewQuantity = lnCurrentQuantity;
		}
	break;
	case 4:// onBlur
	//lnNewQuantity--;
		if(lnNewQuantity = '')
		{
		lnNewQuantity = pnMin;
		}
	break;
	default:// ensuring a typed quantity remains within the parameters defined
	//if (lnCurrentQuantity > pnMax || lnCurrentQuantity < pnMin)
	//{
	//alert("Please set the quantity as a number between " + pnMin + " and " + pnMax + '\n' + "The quantity will now be set to " + pnMin) ;
	lnNewQuantity = pnMin;
	//}
	break;
	}
document.getElementById(pcID).value = lnNewQuantity;
}