需求：
1：更改django框架的admin登录窗口标题
2：在admin登录窗口中添加验证码功能
3：验证码允许点击更换
步骤如下：
1:安装插件以及在安装列表中添加插件
2:自定义表单forms.py
3:创建login.html文件(复制django内置的login.html文件进行更改)
4:在admin.py文件中进行修改（编写登录窗口的信息）
5:对主项目中的urls.py进行修改
6:登录后台–需要验证码
7:settings.py文件中设置验证码的大小和长度(自定义验证码的规格)

B视频地址

1:安装插件以及在安装列表中添加插件

pip install  django-simple-captcha

INSTALLED_APPS = [  
    # 使用多合一有点慢  
    # 'multi_captcha_admin',# 多合一验证码  
    'import_export', # 导出excel插件位置  
    'django.contrib.admin',  
    'django.contrib.auth',  
    'django.contrib.contenttypes',  
    'django.contrib.sessions',  
    'django.contrib.messages',  
    'django.contrib.staticfiles',  
    'app.apps.AppConfig',  
    'userprofile.apps.UserprofileConfig', # user表额外一对一表  
    'store.apps.StoreConfig',  
    'ownorder.apps.OwnorderConfig',  
    'outsourcing.apps.OutsourcingConfig',  
    'captcha',# 验证码  
]

2:自定义表单

from django.contrib.auth.forms import AuthenticationForm  
from captcha.fields import CaptchaField  
  
  
class AppAuthenticationForm(AuthenticationForm):  
    captcha = CaptchaField()

3:创建login.html文件

复制django包中自带的login.html文件中的代码到这里新建的login.html文件中

django自带的login.html文件代码如下

{% extends "admin/base_site.html" %}  
{% load i18n static %}  
  
{% block extrastyle %}{{ block.super }}<link rel="stylesheet" href="{% static "admin/css/login.css" %}">  
{{ form.media }}  
{% endblock %}  
  
{% block bodyclass %}{{ block.super }} login{% endblock %}  
  
{% block usertools %}{% endblock %}  
  
{% block nav-global %}{% endblock %}  
  
{% block nav-sidebar %}{% endblock %}  
  
{% block content_title %}{% endblock %}  
  
{% block nav-breadcrumbs %}{% endblock %}  
  
{% block content %}  
{% if form.errors and not form.non_field_errors %}  
<p class="errornote">  
{% blocktranslate count counter=form.errors.items|length %}Please correct the error below.{% plural %}Please correct the errors below.{% endblocktranslate %}  
</p>  
{% endif %}  
  
{% if form.non_field_errors %}  
{% for error in form.non_field_errors %}  
<p class="errornote">  
    {{ error }}  
</p>  
{% endfor %}  
{% endif %}  
  
<div id="content-main">  
  
{% if user.is_authenticated %}  
<p class="errornote">  
{% blocktranslate trimmed %}  
    You are authenticated as {{ username }}, but are not authorized to  
    access this page. Would you like to login to a different account?  
{% endblocktranslate %}  
</p>  
{% endif %}  
  
<form action="{{ app_path }}" method="post" id="login-form">{% csrf_token %}  
  <div class="form-row">  
    {{ form.username.errors }}  
    {{ form.username.label_tag }} {{ form.username }}  
  </div>  
  <div class="form-row">  
    {{ form.password.errors }}  
    {{ form.password.label_tag }} {{ form.password }}  
    <input type="hidden" name="next" value="{{ next }}">  
  </div>  {% url 'admin_password_reset' as password_reset_url %}  
  {% if password_reset_url %}  
  <div class="password-reset-link">  
    <a href="{{ password_reset_url }}">{% translate 'Forgotten your password or username?' %}</a>  
  </div>  {% endif %}  
  <div class="submit-row">  
    <input type="submit" value="{% translate 'Log in' %}">  
  </div></form>  
  
</div>  
{% endblock %}

修改后
添加验证码块
并且添加点击验证码刷新的功能

{% extends "admin/base_site.html" %}  
{% load i18n static %}  
  
{% block extrastyle %}{{ block.super }}<link rel="stylesheet" href="{% static "admin/css/login.css" %}">  
{{ form.media }}  
{% endblock %}  
  
{% block bodyclass %}{{ block.super }} login{% endblock %}  
  
{% block usertools %}{% endblock %}  
  
{% block nav-global %}{% endblock %}  
  
{% block nav-sidebar %}{% endblock %}  
  
{% block content_title %}{% endblock %}  
  
{% block nav-breadcrumbs %}{% endblock %}  
  
{% block content %}  
{% if form.errors and not form.non_field_errors %}  
<p class="errornote">  
{% blocktranslate count counter=form.errors.items|length %}Please correct the error below.{% plural %}Please correct the errors below.{% endblocktranslate %}  
</p>  
{% endif %}  
  
{% if form.non_field_errors %}  
{% for error in form.non_field_errors %}  
<p class="errornote">  
    {{ error }}  
</p>  
{% endfor %}  
{% endif %}  
  
<div id="content-main">  
  
{% if user.is_authenticated %}  
<p class="errornote">  
{% blocktranslate trimmed %}  
    You are authenticated as {{ username }}, but are not authorized to  
    access this page. Would you like to login to a different account?  
{% endblocktranslate %}  
</p>  
{% endif %}  
  
<form action="{{ app_path }}" method="post" id="login-form">{% csrf_token %}  
  <div class="form-row">  
    {{ form.username.errors }}  
    {{ form.username.label_tag }} {{ form.username }}  
  </div>  
  <div class="form-row">  
    {{ form.password.errors }}  
    {{ form.password.label_tag }} {{ form.password }}  
    <input type="hidden" name="next" value="{{ next }}">  
  </div>  <div class="form-row">  
    {{ form.captcha.errors }}  
    {{ form.captcha.label_tag }} {{ form.captcha }}  
    <input type="hidden" name="next" value="{{ next }}">  
  </div>  {% url 'admin_password_reset' as password_reset_url %}  
  {% if password_reset_url %}  
  <div class="password-reset-link">  
    <a href="{{ password_reset_url }}">{% translate 'Forgotten your password or username?' %}</a>  
  </div>  {% endif %}  
  <div class="submit-row">  
    <input type="submit" value="{% translate 'Log in' %}">  
  </div>{#添加点击验证码刷新功能#}  
    <script src="{% static '/admin/huadong/jquery-3.6.0.min.js' %}"></script>  
    <script>        $('img.captcha').attr("title", "点击更换验证码");  
        $('img.captcha').click(function () {  
            $.getJSON('/captcha/refresh/', function (json) {  
                // This should update your captcha image src and captcha hidden input  
                console.log(json);  
                $("img.captcha").attr("src", json.image_url);  
                $("#id_captcha_0").val(json.key);  
            });  
            return false;        });  
    </script>  
  
</form>  
  
</div>  
{% endblock %}

验证码刷新功能使用到了jquery.js 我把这个放置到了本地，请自行更换其他版本

4在admin.py文件中进行修改

添加以下代码

# forms中定义的表单 添加了验证码字段  
from .forms import AppAuthenticationForm  
  
class MyAdminSite(admin.AdminSite):  
    # 向django 自带的admin 中使用 自定义的表单  
    login_form = AppAuthenticationForm  
    # 自定义表单的位置  
    login_template = "app/login.html"  
    # 设置后台登陆显示标题--方法1  
    # 登录窗口所使用的显示标头以及网站标题  
    # 浏览器网站窗口显示文字  
    site_title = '业务管理系统'  
    # 登录窗口显示标题文字  
    site_header = '业务管理系统登录'  
    # index_title = '业务管理系统网页标题3'  
    # 添加打开这个管理后台显示的网站标题----窗口标题信息  
    admin.site.site_title = '业务管理系统网页标题'  
    # 添加打开这个管理后台显示的登录窗口网站标题  
    admin.site.site_header = '业务管理系统'  
  
admin_site = MyAdminSite(name="management")

admin_site
对 AdminSite 类进行了子分类，以便我们可以随意修改和覆盖 django 默认管理员的任何模板，而不会影响默认管理员的任何内容，并继承 admin 的所有函数和模板

5对主项目中的urls.py进行修改

from django.contrib import admin  
from django.urls import path, include  
  
# 添加自定义的登录  
from app.admin import AppAuthenticationForm  
  
admin.site.login_form = AppAuthenticationForm  
admin.site.login_template = "app/login.html"  
  
# admin.autodiscover()  
# 在 Django 中，是一个函数，用于自动发现和注册 Django 项目中所有已安装应用的管理配置。此函数通常在项目的urls.py文件中调用。  
  
urlpatterns = [  
    path('admin/', admin.site.urls),  
    path('captcha/', include('captcha.urls')),  
]

6登录后台–需要验证码

http://127.0.0.1:8000/admin/login/?next=/admin/

7:settings.py文件中设置验证码的大小和长度

# Font size of the captcha text
CAPTCHA_FONT_SIZE = 40

# Length of the captcha text (number of characters)
CAPTCHA_LENGTH = 12

# Number of attempts a user can try before captcha protection is enforced
CAPTCHA_MAX_ATTEMPTS = 3

# Timeout (in minutes) after which the captcha session expires
CAPTCHA_TIMEOUT = 5

# Image dimensions of the captcha image
CAPTCHA_IMAGE_SIZE = (200, 100)

# Custom image size for captcha (tuple of width and height)
# If set, overrides CAPTCHA_IMAGE_SIZE
# CAPTCHA_IMAGE_SIZE = (width, height)

# Length of the generated audio captcha
CAPTCHA_AUDIO_LENGTH = 5

# Case sensitivity of the captcha text
CAPTCHA_CASE_SENSITIVE = False

# Characters allowed in the captcha text
CAPTCHA_ALLOWED_CHARS = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789'

# Timeout for the cache (in seconds) for storing captcha
CAPTCHA_TIMEOUT = 5 * 60  # 5 minutes

# Directory where temporary captcha images/audio are stored
CAPTCHA_OUTPUT_FORMAT = '%(time)s%(part)s.png'
CAPTCHA_IMAGE_DIR = 'captcha'

# Custom directory for storing captcha images/audio
# CAPTCHA_IMAGE_DIR = 'custom_captcha_dir'

# Timeout for the cache (in seconds) for storing captcha
CAPTCHA_TIMEOUT = 5 * 60  # 5 minutes

# Number of seconds for which the captcha cookie is valid
CAPTCHA_COOKIE_TIMEOUT = CAPTCHA_TIMEOUT

# Length of the hash used for storing the captcha image/audio in the cache
CAPTCHA_CACHE_KEY_LENGTH = 16

# The challenge text for the captcha audio
CAPTCHA_CHALLENGE_FUNCT = 'captcha.helpers.math_challenge'

# Function to generate captcha audio
CAPTCHA_AUDIO_CHALLENGE_FUNCT = 'captcha.helpers.math_audio_challenge'

# Custom challenge function for captcha text
# CAPTCHA_CHALLENGE_FUNCT = 'myapp.utils.my_challenge_function'

Now that I've added the following code to my [django] project, please check it for me, please say what is added and what is missing, and where is it used?
froms.py code:
from django.contrib.auth.forms import AuthenticationForm  
from captcha.fields import CaptchaField  
  
  
class AppAuthenticationForm(AuthenticationForm):  
    captcha = CaptchaField()

admin.py code:
from django.contrib import admin  
  

from .forms import AppAuthenticationForm  
  
class MyAdminSite(admin.AdminSite):  
    login_form = AppAuthenticationForm  
    login_template = "weidanyewu/login.html"  
    site_title = 'sy'  
    site_header = 'sy'  
    admin.site.site_title = 'sy'  
    admin.site.site_header = 'sy'  
admin_site = MyAdminSite(name="management")