Question

我有“ Club”类和“ Match”类两个模型，并且具有俱乐部的外键但是我不能通过“匹配”类中的“ score_local”和“ score_visitor”来增加“ Club”类中的“获胜”字段（或平局或输掉）。我该怎么办

class Club(models.Model):
    league_names = models.ForeignKey(League, on_delete= models.CASCADE, related_name='club')
    name = models.CharField(max_length=100)
    logo = models.ImageField(upload_to='media/core', max_length=255, null=True, blank=True)
    year_of_establishment = models.IntegerField(default=1900)
    won = models.IntegerField(default=0)
    draw = models.IntegerField(default=0)
    lost = models.IntegerField(default=0)

    def CalcPoints(self):
         return self.won*3 + self.draw            

    total_points = property(CalcPoints)

class Match(models.Model):
    play_date = models.DateTimeField('play date')
    occasion = models.ForeignKey(League, on_delete=models.CASCADE, related_name='match')
    club_visitor = models.ForeignKey(Club, on_delete=models.CASCADE, related_name='match_club_visitor')
    club_local = models.ForeignKey(Club, on_delete=models.CASCADE, related_name='match_club_local')
    score_visitor = models.IntegerField()
    score_local = models.IntegerField()

Answer 1

即使在同一模型上，也无法在字段之间建立关系，但是您可以覆盖Match中的save方法，您可以实现一个signal处理函数，在每个{{1 }}被保存。

match

Answer 2

您将需要以某种方式更新模型的字段。

我会建议类似的东西

首先，编写一个从数据库为您提供俱乐部的功能：

def get_clubs(local_club_id, visitor_club_id):
    local_club = Club.objects.filter(pk=self.local_club_id)[0]
    visitor_club = Club.objects.filter(pk=self.visitor_club_id)[0]
    return local_club, visitor_club

然后，您可以适当地（在您的views.py中）更新胜负：

def update_scores(request):
    match = request.match
    club_local, club_visitor = get_clubs(match.club_local.pk, match.club_visitor.pk)
    if match.score_local > match.score_visitor:
        # home team won
        club_local.update(won=match.club_local.won + 1)
        club_visitor.update(lost=match.club_visitor.lost + 1)
    elif match.score_visitor > match.score_local:
        # away team won
        club_visitor.update(won=match.club_visitor.won + 1)
        club_local.update(lost=match.club_local.lost + 1)
    else:
        # it's a draw
        club_local.update(draw=match.club_local.draw + 1)
        club_visitor.update(draw=match.club_visitor.draw + 1)

此后，您的属性函数应会按预期工作。

如何在具有不同django类的两个字段之间建立关系？

2 个答案: