创建一个参考号码，然后当条件满足，复位计数

Question

我已经创建了一段代码，我的系统生成编号。我可以按照我想要的方式生成它。但我没有想法如何重置时年由1

加入我重写Django的保存功能所以每次我打的时间保存，它会为我参考它的票。

def save(self, force_insert=False, force_update=False): 
    yr = datetime.now() 
    yrnum = yr.strftime("%Y%m%d") 
    if self.system == 'Software': 
     self.refNo = 'S%s-%03d' % (yrnum, int(self.ticketCount)) #ticketCount is a CharField that stores the count of the rows, the thing I want to reset when yrnum is added by 1. 
    else: 
     self.refNo = 'A%s-%03d' % (yrnum, int(self.ticketCount)) 
    super(tblTicket, self).save(force_insert, force_update) 

它的输出是：

A20151021-001 
A20151021-002 
A20151021-003 

然后当打之年的变化，我想序列重置为1。像这样：

A20151021-115 
A20151121-116 
A20151221-117 
... 
A20160101-001 
A20160101-002 
A20160101-003 

Answer 1

一个选项是，你可以给初始化对象时，既节约了本年度为整数模型的IntegerField（称为currentYear）。然后，在您的保存功能中，您可以执行如下检查：

year = datetime.date.today().year 
if year > self.currentYear: # This means it is one year ahead of currentYear (this will occur on Jan 1st of every year) 
    self.currentYear += 1 # currentYear is now the current year again. 
    self.ticketCount = 1 # reset the ticket count for the new year