django子代理日期时间字段

Question

我使用的模型有一个名为start_time和finish_time的字段，这两个字段都是DateTimeField，我试图通过用start_time减去finish_time来计算响应时间。

壳内：

>>> obj = Quizgame.objects.get(user=harry)
>>> start = obj.start_time
>>> end = obj.finish_time
>>> result = end - start
>>> result
datetime.timedelta(seconds=31, microseconds=912224)

但是在django视图中，当我执行此操作时，我会得到一个错误，即-："method"one_answers"datetime.datetime"的操作数类型不受支持

views.py
def final_part(request):
obj = Quizgame.objects.get(user=request.user)
start = obj.start_time
end = obj.end_time
result = end - start
return HttpResponse(result)

models.py
class Quizgame(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
total_score = models.DecimalField("Total score", default=0, decimal_places=2, max_digits=6)
start_time = models.DateTimeField(auto_now_add=True)
finish_time = models.DateTimeField(null=True)

我后来用datetime.datetime.now((设置了完成时间

Answer 1

您使用了obj.end_time而不是obj.finish_time

def final_part(request):
obj = Quizgame.objects.get(user=request.user)
start = obj.start_time
end = obj.finish_time
result = end - start
return HttpResponse(result)