我想用下一个和上一个课程打开课程详细信息,但我的尝试不起作用,我给出了 404 错误,当我删除尝试时,除了我给出“QuerySet”对象没有属性错误,并说错误来自 counted_views
views.py:
```
def course_detail(request,id):
try:
course = Courses.objects.get(id=id)
id_list = []
course = Courses.objects.filter(status = True)
for cr in course :
id_list.append(cr.id)
if id_list[0] == id:
next_course = Courses.objects.get(id=id_list[1])
previous_course =None
elif id_list[-1] == id:
next_course = None
previous_course = Courses.objects.get(id=id_list[-2])
else:
next_course = Courses.objects.get(id=id_list[id_list.index(id)+1])
previous_course = Courses.objects.get(id=id_list[id_list.index(id)-1])
course.counted_views += 1
course.save()
context = {
'course': course,
'next_course': next_course,
'previous_course': previous_course,
}
return render(request,"courses/course-details.html",context=context)
except:
return render(request,'courses/404.html')
```
urls.py:
```
from django.urls import path
from .views import *
app_name = 'course'
urlpatterns = [
path('',Maincourse,name='courses'),
path('category/<str:cat>',Maincourse,name='course_cat'),
path('teacher/<str:teacher>',Maincourse,name='course_teacher'),
path('search/',Maincourse,name='course_search'),
path('course_detail/<int:id>',course_detail,name='course_detail'),
]```
models.py:
```class Courses(models.Model):
title = models.CharField(max_length=40)
content = models.TextField(max_length=1000)
teacher = models.ForeignKey(Trainer,on_delete=models.CASCADE)
price = models.IntegerField(default=0)
image = models.ImageField(upload_to='courses',default='default.jpg')
category = models.ManyToManyField(Category)
counted_views = models.IntegerField(default=0)
counted_likes = models.IntegerField(default=0)
status = models.BooleanField(default=False)
created_date = models.DateTimeField(auto_now_add = True)
updated_date = models.DateTimeField(auto_now = True)
available_seats = models.IntegerField(default = 0)
schedule = models.DateTimeField(default=datetime.datetime.now())
```
您最初声明了一个变量
course
,用于获取一个对象,但随后将其重新分配给一个查询集,该查询集现在不再是一个对象,而是一个对象列表。您可以从以下位置编辑此行:
course = Courses.objects.filter(status = True)
致:
courses = Courses.objects.filter(status = True)
id_list = [cr.id for cr in courses]
顺便说一句,按照惯例,模型以单数命名,因此
Course
而不是 Courses
。