Django 中的 TypeError 和 NoReverseMatch答案

【问题标题】：TypeError and NoReverseMatch in djangoDjango 中的 TypeError 和 NoReverseMatch
【发布时间】：2020-12-24 12:52:04
【问题描述】：

当我转到/projects 时，我在/projects/Reverse 得到 NoReverseMatch，因为找不到“详细信息”。 'detail' 不是有效的视图函数或模式名称。

当我转到 /projects/some number 时，我在 /projects/1/ 处收到 TypeError “项目”对象不可迭代

路径

main
   migrations
   templates
           detail.html
           home.html
           proceed.html
           project.html
   __init_.py
   admin.py
   apps.py
   models.py
   tests.py
   views.py
portfolio
     __init_.py
     asgi.py
     settings.py
     urls.py
     wsgi.py
db.sqlite3
manage.py

views.py

from django.shortcuts import render, get_object_or_404
from .models import Project
# Create your views here.


def home(request):
    return render(request, "home/home.html")

def project(request):
    projects = Project.objects.all()
    return render(request, "home/project.html", {'projects':projects })


def detail(request, project_id):
    oof = get_object_or_404(Project, pk=project_id)
    return render(request, 'home/detail.html', {'projectss': oof})

detail.html

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css" type="text/css">
  <link rel="stylesheet" href="https://static.pingendo.com/bootstrap/bootstrap-4.3.1.css">
</head>

<body >
  <div class="py-5" style=" background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: center center; background-size: 100%;  background-repeat: repeat;">
    <div class="container">
      <div class="row">
        <div class="text-center mx-auto col-md-12">
          <h1 class="text-light">Proceed to external site</h1>
        </div>
      </div>
    </div>
  </div>
  <div class="py-5 text-center" style=" background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: top left;  background-size: 100%;  background-repeat: repeat;">
    <div class="container">
      <div class="row">
        {% for project in projectss %}
        <div class="mx-auto col-lg-5 col-md-7 col-10">
            <h1 class="text-white mb-5">{project.title}</h1>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <h3 class="mb-3 text-white">{project.point1}</h3>
            <a class="btn btn-primary btn-lg mt-5" href="{project.url}">Go to site</a>
          </div>
        {% endfor %}
      </div>
    </div>
  </div>
  <div class="py-3" style=" background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: top left;  background-size: 100%;  background-repeat: repeat;">
    <div class="container">
      <div class="row">
        <div class="col-md-12 text-center">
          <p class="mb-0 pb-3"> <a href="mailto:work.arpit7@gmail.com">work.arpit7@gmail.com</a> </p><big>
            <p class="text-white">Follow me on social media!</p>
          </big>
        </div>
      </div>
      <div class="row" style="padding-bottom: 2%">
        <div class="col-md-12 d-flex align-items-center justify-content-center my-3"> <a href="#">
            <i class="d-block fa fa-instagram text-muted fa-lg mx-2"></i>
          </a> <a href="#">
            <i class="d-block fa fa-reddit text-muted fa-lg mx-2"></i>
          </a> <a href="#">
            <i class="d-block fa fa-twitter text-muted fa-lg ml-2"></i>
          </a> </div>
      </div>
    </div>
  </div>
  <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>

</html>

project.html

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css" type="text/css">
  <link rel="stylesheet" href="https://static.pingendo.com/bootstrap/bootstrap-4.3.1.css">
</head>

<body>
  <nav class="navbar navbar-expand-lg navbar-dark bg-dark" style="  background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: top left;  background-size: 100%;  background-repeat: repeat;">
    <div class="container"> <a class="navbar-brand" href="#">
        <i class="fa d-inline fa-lg fa-circle-o"></i>
        <b>Arpit's portfolio</b>
      </a> <button class="navbar-toggler navbar-toggler-right border-0" type="button" data-toggle="collapse" data-target="#navbar11">
        <span class="navbar-toggler-icon"></span>
      </button>
      <div class="collapse navbar-collapse" id="navbar11">
        <ul class="navbar-nav ml-auto">
          <li class="nav-item"> <a class="nav-link text-white" href="#">Portfolio projects</a> </li>
          <li class="nav-item"> <a class="nav-link text-white" href="#">Blog</a> </li>
          <li class="nav-item"> <a class="nav-link text-white" href="#">Contact</a> </li>
        </ul> <a class="btn btn-primary navbar-btn ml-md-2 text-white">Hire me</a>
      </div>
    </div>
  </nav>
  <div class="py-5" style=" background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: center center; background-size: 100%;  background-repeat: repeat;">
    <div class="container">
      <div class="row">
        <div class="text-center mx-auto col-md-12">
          <h1 class="text-light">Some of my portfolio projects</h1>
        </div>
      </div>
    </div>
  </div>
<div class="py-5" style="   background-image: linear-gradient(to bottom, rgb(0,0,0), rgb(0,0,0));   background-position: center center; background-size: 100%;  background-repeat: repeat;" >
    <div class="container">
        <div class="row">
            <div class="text-center container">
                <div class="row" >
                    {% for project in projects %}
                    <div class="card mx-5" style="width: 30%; height:43%; margin-bottom: 5%;">
                        <div class="card-body" >
                          <h3 class="card-title text-dark">{{ project.title }}</h3>
                          <h5 class="card-text text-dark mt-4">{{ project.description }}</h5>
                          <h3 style="margin-top : 12%">Made using {{ project.madef }}</h3>
                          <a href="{% url 'detail' project.id %}" class="btn btn-primary" style="margin-top : 18%">Check out</a>
                        </div>
                      </div>
                    {% endfor %}
                </div>
            </div>
        </div>
    </div>
</div>
<div class="py-3" style="   background-image: linear-gradient(to bottom, rgb(0, 0, 0), rgb(0, 0, 0));   background-position: top left;  background-size: 100%;  background-repeat: repeat;">
    <div class="container">
      <div class="row">
        <div class="col-md-12 text-center">
          <p class="mb-0 pb-3"> <a href="mailto:work.arpit7@gmail.com">work.arpit7@gmail.com</a> </p><big>
            <p class="text-white">Follow me on social media!</p>
          </big>
        </div>
      </div>
      <div class="row">
        <div class="col-md-12 d-flex align-items-center justify-content-center my-3"> <a href="#">
            <i class="d-block fa fa-instagram text-muted fa-lg mx-2"></i>
          </a> <a href="#">
            <i class="d-block fa fa-reddit text-muted fa-lg mx-2"></i>
          </a> <a href="#">
            <i class="d-block fa fa-twitter text-muted fa-lg ml-2"></i>
          </a> </div>
      </div>
    </div>
  </div>
  <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>

</html>

urls.py

"""portfolio URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/3.0/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  path('', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  path('', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.urls import include, path
    2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
"""
from django.contrib import admin
from django.urls import path
from main import views



urlpatterns = [
    path('admin/', admin.site.urls),
    path('', views.home),
    path('projects/', views.project),
    path('projects/<int:project_id>/', views.detail)
]

settings.py

"""
Django settings for portfolio project.

Generated by 'django-admin startproject' using Django 3.0.10.

For more information on this file, see
https://docs.djangoproject.com/en/3.0/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/3.0/ref/settings/
"""

import os

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.0/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = '_4d4kcc1u=5xch1a_un*j2e8^_ca7d1(r+d60@_67o^l&@vu0d'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'main'
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'portfolio.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'portfolio.wsgi.application'


# Database
# https://docs.djangoproject.com/en/3.0/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}


# Password validation
# https://docs.djangoproject.com/en/3.0/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/3.0/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.0/howto/static-files/

STATIC_URL = '/static/'

models.py

from django.db import models

# Create your models here.

class Project(models.Model):
    title = models.CharField(max_length=100)
    description = models.CharField(max_length=100000000)
    url = models.CharField(max_length=100000000000000, blank=True)
    madef = models.CharField(max_length=100, blank=True)
    point1 = models.CharField(max_length=100000000000000, blank=True)
    point2 = models.CharField(max_length=100000000000000, blank=True)
    point3 = models.CharField(max_length=100000000000000, blank=True)
    point4 = models.CharField(max_length=100000000000000, blank=True)
    point5 = models.CharField(max_length=100000000000000, blank=True)
    point6 = models.CharField(max_length=100000000000000, blank=True)
    point7 = models.CharField(max_length=100000000000000, blank=True)
    point8 = models.CharField(max_length=100000000000000, blank=True)


    def __str__(self):
        return  self.title

admin.py

from django.contrib import admin
from .models import Project
# Register your models here.

admin.site.register(Project)

我对此很陌生，我不知道我在哪里犯了错误我正在使用 Djnago 3.0.10

【问题讨论】：

我认为您没有正确定义您的模板目录。它不知道去哪里获取您的模板。尝试在您的 TEMPLATES['DIRS'] 中添加 'main/templates/' 在您的 settings.py 中
你应该创建一个minimal reproducible example 而不是发布你的整个代码

标签： python django

【解决方案1】：

写下去没有意义：

{% for project in projectss %}
    …
{% endfor %}

因为在您的详细视图中，projectss 是单个 Project *对象，而不是QuerySet 对象。所以你不能迭代它。您只需删除 {% for … %}，改用 projectss，所以：

<div class="row">
    <div class="mx-auto col-lg-5 col-md-7 col-10">
        <h1 class="text-white mb-5">{{ projectss.title }}</h1>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <h3 class="mb-3 text-white">{{ projectss.point1 }}</h3>
        <a class="btn btn-primary btn-lg mt-5" href="{{ projectss.url }}">Go to site</a>
    </div>
</div>

要渲染一个变量，你使用双大括号，所以{{ … }}，而不是~~{ … }~~。

对于NoReverseMatch错误，你需要给你的视图一个合适的名字，所以：

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', views.home),
    path('projects/', views.project),
    path('projects/<int:project_id>/', views.detail, name='detail')
]

【讨论】：