Python 如何在 django 中的表单上显示更多对象信息

最简单的方法就是覆盖__str__方法，并包括购买价格:

class Holdings(models.Model):
    student = models.ForeignKey(Student, on_delete=models.CASCADE)
    symbol = models.CharField(max_length=10)
    purchase_price = models.DecimalField(max_digits=10, decimal_places=2)

    class Meta:
        verbose_name_plural = "Holdings"
        ordering = ['symbol']

    def __str__(self):
        return f'{self.symbol} ({self.purchase_price})'

过滤可以更高效地完成，不过使用以下选项:

class SellForm(forms.Form):
    symbol = forms.ModelChoiceField(
        queryset=None,
        widget=forms.Select(
            attrs={
                'class': 'form-control',
                'placeholder': 'Symbol',
                'autofocus': 'autofocus',
            }
        ),
    )

    def __init__(self, *args, request, **kwargs):
        super(SellForm, self).__init__(*args, **kwargs)
        self.fields['symbol'].queryset = Holdings.objects.filter(
            student__user=self.request.user
        )

因为这将阻止为用户获取Student对象的查询，或者我们可以使用:

class SellForm(forms.Form):
    symbol = forms.ModelChoiceField(
        queryset=None,
        widget=forms.Select(
            attrs={
                'class': 'form-control',
                'placeholder': 'Symbol',
                'autofocus': 'autofocus',
            }
        ),
    )

    def __init__(self, *args, request, **kwargs):
        super(SellForm, self).__init__(*args, **kwargs)
        self.fields['symbol'].queryset = Holdings.objects.filter(
            student_id=self.request.user.student_id
        )