在模板中显示计算字段(Django)

from django.db import models

class Product(models.Model):
    name = models.CharField(max_length=100)
    price = models.DecimalField(max_digits=10, decimal_places=2)
    discount = models.DecimalField(max_digits=5, decimal_places=2, default=0)

from django.shortcuts import render
from .models import Product

def product_list(request):
    products = Product.objects.all()
    return render(request, 'product_list.html', {'products': products})

from django import template

register = template.Library()

@register.simple_tag
def calculate_discounted_price(price, discount):
    return price * (1 - discount / 100)

{% load custom_tags %}

<ul>
{% for product in products %}
    <li>{{ product.name }} - 折扣价格: {% calculate_discounted_price product.price product.discount %}</li>
{% endfor %}
</ul>

<ul>
{% for product in products %}
    <li>{{ product.name }} - 折扣价格: {{ product.price|floatformat:2 }} * (1 - {{ product.discount|floatformat:2 }}/100) = {{ product.price|mul:(1 - product.discount|div:100)|floatformat:2 }}</li>
{% endfor %}
</ul>

def product_list(request):
    products = Product.objects.all().annotate(discounted_price=models.ExpressionWrapper(models.F('price') * (1 - models.F('discount') / 100), output_field=models.DecimalField()))
    return render(request, 'product_list.html', {'products': products})

<ul>
{% for product in products %}
    <li>{{ product.name }} - 折扣价格: {{ product.discounted_price }}</li>
{% endfor %}
</ul>