Blueprint简介
Blueprint它是Flask项目的一种组件式开发，可以在一个应用内或跨越 多个项目共用蓝图。使用蓝图可以极大地简化大型应用的开发难度，也为Flask扩展 提供了一种在应用中注册服务的集中式机制。 模块化管理程序路由是它的特色，它使程序结构清晰、简单易懂。但是一个Blueprint并不是一个完整的应用，它不能独立于应用运行，而必须要注册到某一个应用中。
由于只是演示蓝图的基本用法，所以这里以展示用户表，登陆认证，编辑用户，删除用户，新增用户来模拟多个模块作为演示。
环境搭建：
1、创建项目damo_2，在该项目下创建static（存放图片，css样式，js脚本等）、templates（HTML文件）两个目录。
2、新建一个settings.py的配置文件，配置文件中存放用户表
USER_INFO = [{'aaa':'111'},{'bbb':'222'},{'ccc':'333'}] # 模拟数据库中的用户表一、函数的方式（FBV）：
1、展示用户表
1.1创建show.py
from flask import Blueprint,render_template
from settings import USER_INFO
show_app = Blueprint('show_app',__name__)
@show_app.route('/show_page')
def show_page():
return render_template('show_page.html',user_info=USER_INFO)1.2在templates目录下创建show_page.html
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3 style="margin-left: 320px">用户详情表</h3>
<form action="">
<table border="1px">
<thead>
<tr>
<th style="width: 150px;">序号</th>
<th style="width: 150px;">用户</th>
<th style="width: 150px;">密码</th>
<th style="width: 150px;">操作</th>
</tr>
</thead>
<tbody>
{% for user_dict in user_info %}
<tr>
<td style="text-align: center">{{ loop.index0 }}</td>
{% for user in user_dict %}
<td style="text-align: center">{{ user }}</td>
<td style="text-align: center">{{ user_dict.get(user) }}</td>
{% endfor %}
<td style="text-align: center">
<a href="/edit_user?id={{ loop.index0 }}">编辑</a>
|
<a href="/del_user?id={{ loop.index0 }}">删除</a>
</td>
</tr>
{% endfor %}
</tbody>
</table>
<br>
<a href="/add_user">新增</a>
</form>
</body>
</html>2、新增用户
2.1创建add_user.py
from flask import Blueprint, request, render_template, redirect
from settings import USER_INFO
add_user_app = Blueprint('add_user', '__name__')
@add_user_app.route('/add_user', methods=['GET', 'POST'])
def add_user():
if request.method == 'POST':
user = request.form.get('username')
pwd = request.form.get('password')
USER_INFO.append({user: pwd})
return redirect('/show_page')
else:
return render_template('add_user.html')2.2在templates目录下创建add_user.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="" method="post">
<h3>新增用户界面</h3>
用户名：<input type="text" name="username">
密码：<input type="password" name="password">
<button>新增</button>
</form>
</body>
</html>3、编辑用户
3.1创建edit_user.py文件
from flask import Blueprint, render_template, request, redirect
from settings import USER_INFO
edit_user_app = Blueprint('edit_user', '__name__')
@edit_user_app.route('/edit_user', methods=['GET', 'POST'])
def edit_user():
uid = int(request.args.get('id'))
if request.method == 'POST':
user = request.form.get('username')
pwd = request.form.get('password')
nlen = len(USER_INFO)
if 0 > uid or uid >= nlen:
return f'索引不存在,索引范围是:0-{nlen - 1}'
else:
USER_INFO[uid] = {user: pwd}
return redirect('/show_page')
else:
user_info = USER_INFO[uid]
return render_template('edit_user.html', user_info=user_info)3.2在templates目录下创建edit_user.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="" method="post">
<h3>编辑用户界面</h3>
{% for user in user_info %}
用户名：<input type="text" name="username" value="{{ user }}">
密码：<input type="password" name="password" value="{{ user_info[user] }}">
{% endfor %}
<button>保存</button>
</form>
</body>
</html>4、删除用户
4.1创建del_user.py
from flask import Blueprint,request,render_template,redirect
from settings import USER_INFO
del_user_app = Blueprint('del_user','__name__')
@del_user_app.route('/del_user')
def del_user():
uid = int(request.args.get('id'))
USER_INFO.pop(uid)
return redirect('/show_page')5、创建damo_2.py主文件
from flask import Flask, session, request, redirect, render_template
from flask import session
from show import show_app
from index import index_app
from add_user import add_user_app
from del_user import del_user_app
from edit_user import edit_user_app
from login import login_app
user_app = Flask('__name__')
user_app.secret_key = '~!@#$%^&*'
user_app.config['DEBUG'] = True
@user_app.before_request
def session_check(): # 中间件用户登陆认证，用户必须登录后才能访问展示页面
if session.get('user') or request.path == '/login':
return None
else:
return redirect('/login')
@user_app.after_request
def response_after(response):
return response
user_app.register_blueprint(index_app) # 注册公共展示页面
user_app.register_blueprint(show_app) # 注册用户详情页面
user_app.register_blueprint(add_user_app) # 注册新增用户页面
user_app.register_blueprint(del_user_app) # 注册删除用户页面
user_app.register_blueprint(edit_user_app) # 注册编辑用户页面
user_app.register_blueprint(login_app) # 注册用户登陆页面
@user_app.errorhandler(404) # 404错误页面
def error404(error_msg):
return render_template('error404.html')
user_app.run()二、使用类的方式（CBV）
1、修改展示页面show.py
from flask import Blueprint, render_template
from settings import USER_INFO
from flask import views
show_app = Blueprint('show_app',__name__)
class ShowPage(views.MethodView):
def get(self):
return render_template('show_page.html', user_info=USER_INFO)
show_app.add_url_rule('/show_page', view_func=ShowPage.as_view(name='show_page'))2、修改新增用户add_user.py
from flask import Blueprint, request, render_template, redirect
from settings import USER_INFO
from flask import views
add_user_app = Blueprint('add_user', '__name__')
class AddUser(views.MethodView):
def get(self):
return render_template('add_user.html')
def post(self):
user = request.form.get('username')
pwd = request.form.get('password')
USER_INFO.append({user: pwd})
return redirect('/show_page')
add_user_app.add_url_rule('/add_user',view_func=AddUser.as_view(name='add_user'))3、修改编辑用户edit_user.py
from flask import Blueprint, render_template, request, redirect
from settings import USER_INFO
from flask import views
edit_user_app = Blueprint('edit_user', '__name__')
class EditUser(views.MethodView):
def get(self):
uid = int(request.args.get('id'))
user_info = USER_INFO[uid]
return render_template('edit_user.html', user_info=user_info)
def post(self):
uid = int(request.args.get('id'))
user = request.form.get('username')
pwd = request.form.get('password')
nlen = len(USER_INFO)
if 0 > uid or uid >= nlen:
return f'索引不存在,索引范围是:0-{nlen - 1}'
else:
USER_INFO[uid] = {user: pwd}
return redirect('/show_page')
edit_user_app.add_url_rule('/edit_user',view_func=EditUser.as_view(name='edit_view'))4、修改删除用户del_user.py
from flask import Blueprint,request,render_template,redirect
from settings import USER_INFO
from flask import views
del_user_app = Blueprint('del_user','__name__')
class DelUser(views.MethodView):
def get(self):
uid = int(request.args.get('id'))
USER_INFO.pop(uid)
return redirect('/show_page')
del_user_app.add_url_rule('/del_user',view_func=DelUser.as_view(name='del_user'))页面展示如下：
