User input Delivery_Date -> ScheduleDeliveryDate_Validations

if(row.Delivery_Date <= zoho.currentdate)
{
	alert "Please enter future dates only";
	row.Delivery_Date=null;
}
else if(row.Delivery_Date != null)
{
	check_same_date = 0;
	coun = 1;
	for each  rec in input.Despatch_Schedule
	{
		if(rec.Part_No == row.Part_No && rec.Delivery_Date == row.Delivery_Date)
		{
			check_same_date = check_same_date + 1;
		}
	}
	//alert check_same_date;
	if(check_same_date == 2)
	{
		alert "Already you have chosen the same date for the same item.Please Choose different delivery date";
		row.Delivery_Date=null;
	}
}