小编Ste*_*en 的帖子

我有一个已支付的价值清单,并希望显示已支付的总金额.我使用Aggregation和Sum来一起计算值.问题是,我只想要打印出总值,但是聚合打印出:( {'amount__sum': 480.0}480.0是总增加值.

在我看来,我有:

    from django.db.models import Sum

    total_paid = Payment.objects.all.aggregate(Sum('amount'))

为了显示页面上的值,我有一个mako模板,其中包含以下内容:

    <p><strong>Total Paid:</strong> ${total_paid}</p>

如何让它显示480.0而不是{'amount__sum': 480.0}？

我有一个表单,使用不同的模型并使用直通(中间)模型:

class CourseBooking(BaseModel):
    '''Intermediary model linking a person on a course with the related booking'''

    course = ForeignKey('ScheduledCourse')
    customer = ForeignKey('Customer')
    booking = ForeignKey('GroupBooking', blank=True, null=True)

表单使用基本表单而不是模型表单,手动添加字段:

class CourseBookingForm(Form):

    course = ModelChoiceField(queryset=ScheduledCourse.objects.all())    
    title = CharField(
            max_length=255,
            widget=Select(choices=TITLE_CHOICES),
            required=False
            )
    gender = CharField(
            max_length=255,
            widget=Select(choices=GENDER_CHOICES),
            required=False
            )
    first_name = CharField(max_length=255)
    surname = CharField( max_length=255)
    dob = DateField(required=False)    
    medical = CharField(required=False, widget = forms.Textarea(attrs={'rows': '4'}))
    # miscellaneous notes
    notes = CharField(required=False, widget = forms.Textarea(attrs={'rows': '4'}))
    email = EmailField(required=False)
    phone = CharField(required=False)
    address …