如何在json文件中写入数据？

Question

如何在json文件中写入数据？这是我的尝试：

from django.test import TestCase
from django_dynamic_fixture import G
import content.factories
from django.core import serializers
from content.models import UserProfile, Delivery
from django.contrib.auth.models import User

class DeliveryTest(TestCase):
    def test_sample_data(self):
        for i in range(0,10):
            user = content.factories.UserFactory.create()
            print user
            for j in range(0, 50):
                delivery = content.factories.DeliveryFactory.create(user=user)
                print delivery

                with open("file.json", "w") as out:
                    data = serializers.serialize("json", User.objects.all() ) 

                with open("file.json", "w") as out:
                    data2 = serializers.serialize("json", Delivery.objects.all() )

输出（打印）：http://dpaste.com/hold/923339/

Answer 1

实际上，您并不是在编写数据，而是转换为JSON。对打开的文件调用.write()：

with open("file.json", "w") as out:
    data = serializers.serialize("json", User.objects.all())
    out.write(data)
    data2 = serializers.serialize("json", Delivery.objects.all() )
    out.write(data)

只打开file.json一次；每次用'w'模式打开它进行写入时，它都会首先被擦除。在

或者，get a reference to the serializer并告诉它直接写入打开的文件：

^{pr2}$

哪个更有效。在