Python Flask基础到登录功能的实现代码-巨人网络通讯

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Python Flask基础到登录功能的实现代码

0x01路由

from flask import Flask

app = Flask(__name__)  # flask对象实例化
 
@app.route('/index')    #定义首页
@app.route('/')       #设置默认index
def index():
    return 'hello world!'

@app.route('/home/string:username>')   # 生成home路由,单一传参
def home(username):
    print(username)
    return 'h1>欢迎回家/h1>'

@app.route('/main/string:username>/string:password>') #多个参数传递
def main(username,password):
    print(username)
    print(password)
    return 'h1>welcome/h1>'

def about():
    return  'about page'
app.add_url_rule(rule='/about',view_func=about)  #另一种添加路由的方式

if __name__ == '__main__':
    app.debug = True  #开启debug模式
    app.run()

0x02 模版和静态文件

2.1 文件结构

2.2代码

#app.py
#app.py
from flask import Flask,render_template    #倒入模版

app = Flask(__name__) #声明模版文件夹


@app.route(('/index'))
def index():

  return render_template('index.html') #返回模版

if __name__ == '__main__':
    app.run(debug=True)

!DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>Title/title>
/head>
body>
    h1>hello hello/h1>
    img src="/static/imgs/1.png">
/body>
/html>

2.3 运行效果

0x03 json

from flask import Flask,jsonify

app = Flask(__name__)

@app.route('/')
def index():
    user = {'name':'李三','password':'123'}
    return jsonify(user)

if __name__ == '__main__':
    app.run(debug=True)

3.1运行效果

0x04 重定向

4.1 访问跳转

from flask import Flask, redirect  #导入跳转模块

app = Flask(__name__)

@app.route('/index')
def index():
    return redirect('https://www.baidu.com') #指定跳转路径，访问/index目录即跳到百度首页

@app.route('/home')
def home():
    return 'home page'
if __name__ == '__main__':
    app.run(debug=True)

4.2 打印路由

from flask import Flask,url_for #导入模块

app = Flask(__name__)

@app.route('/index')
def index():
    return 'test'

@app.route('/home')
def home():
    print(url_for('index'))   打印 index路由
    return 'home page'

if __name__ == '__main__':
    app.run(debug=True)

4.3 跳转传参

# 访问home，将name带入index并显示在页面
from flask import Flask,url_for,redirect #导入模块

app = Flask(__name__)

@app.route('/indexstring:name>')
def index(name):
    return 'test %s' % name

@app.route('/home')
def home():
    return redirect(url_for('index',name='admin'))

if __name__ == '__main__':
    app.run(debug=True)

0x05 jinjia2模版

5.1代码

from flask import Flask,render_template    #倒入模版

app = Flask(__name__) #声明模版文件夹


@app.route(('/index'))
def index():
    user = 'admin'
    data = ['111',2,'李三']
    userinfo = {'username':'lisan','password':'12333'}
    return render_template('index.html',user=user,data=data,userinfo=userinfo) #返回模版,传入数据

if __name__ == '__main__':
    app.run(debug=True)

!DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>Title/title>
/head>
body>
  h1>11111/h1>

  {{user}}
  {{data}}   #直接传入

  {% if user == 'admin'%}   #简单逻辑判断
    h1 style="color:red">管理员/h1>
  {% else %}
    h1 style="color:green">普通用户/h1>
  {% endif %}
  hr>

  {% for item in data %}   # for循环
    li>{{item}}/li>
  {% endfor %}

  hr>
  {{ userinfo['username'] }}   
  {{ userinfo['password'] }}

  hr>
  {{ user | upper }}   #字母大写（更多可查阅jinjia2过滤器）
/body>
/html>

5.2 运行效果

0x06 蓝图

目的是为了更好的细分功能模块

6.1代码结构

├── admin
│   └── admin.py
└── app.py

6.2 代码

#admin.py
from flask import Blueprint  导入蓝图模块

admin = Blueprint('admin',__name__,url_prefix='/admin') #对象实例化，url_prefix添加路由前缀，表示若想访问本页相关路由，只能通过形如 xxx/admin/login 访问，不能 xxx/login访问

@admin.route('/register')
def register():
    return '欢迎注册'

@admin.route('/login')
def login():
     return '欢迎登录'

#app.py
from flask import Flask
from admin.admin import admin as admin_blueprint   # 导入蓝图


app = Flask(__name__) #声明模版文件夹
app.register_blueprint(admin_blueprint)  #注册蓝图

@app.route(('/index'))
def index():
    return 'index page'

if __name__ == '__main__':
    app.run(debug=True)

0x07 登录

7.1结构

7.2代码

#web.py
from flask import Flask,render_template,request,redirect,flash,url_for,session
from os import urandom
app = Flask(__name__)
app.config['SECRET_KEY'] = urandom(50)
@app.route('/index')
def index():
    if not session.get('user'):
            flash('请登录后操作','warning')
            return redirect(url_for('login'))
    return render_template('index.html')

@app.route('/login',methods=['GET','POST'])
def login():
    if request.method == 'GET':
        return  render_template('login.html')
    elif request.method == 'POST':
        username = request.form.get('username')
        password = request.form.get('password')

        if username == 'admin' and password == '888888':
            flash('登录成功','success')
            session['user'] = 'admin'
            return redirect(url_for('index'))
        else:
            flash('登录失败','danger')
            return  redirect(url_for('login'))

if __name__ == '__main__':
    app.run(debug=True)

# index.html
!DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>Title/title>
    link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css" rel="external nofollow"  rel="external nofollow"  integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">

!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
script src="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js" integrity="sha384-aJ21OjlMXNL5UyIl/XNwTMqvzeRMZH2w8c5cRVpzpU8Y5bApTppSuUkhZXN0VxHd" crossorigin="anonymous">/script>

/head>
body>
    h1>欢迎你，管理员/h1>
     {% for color, message in get_flashed_messages(with_categories=True) %}
     div class="alert alert-{{color}} alert-dismissible" role="alert">
  button type="button" class="close" data-dismiss="alert" aria-label="Close">span aria-hidden="true">times;/span>/button>
    p>{{message}}/p>
/div>
  {% endfor %}
/body>
/html>

#login.html
!DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>login/title>
  !-- 最新版本的 Bootstrap 核心 CSS 文件 -->
link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css" rel="external nofollow"  rel="external nofollow"  integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">

!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
script src="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js" integrity="sha384-aJ21OjlMXNL5UyIl/XNwTMqvzeRMZH2w8c5cRVpzpU8Y5bApTppSuUkhZXN0VxHd" crossorigin="anonymous">/script>
/head>
body>
  form action="/login" method="post">
    div class='form-group'>
      input type="text" name="username" placeholder="请输入用户名" class="form-control">
    /div>
    div class='form-group'>
      input type="password" name="password" placeholder="请输入密码" class="form-control">
    /div>
    div class="form-group">
      input type="submit" value= "submit" class="btn btn-primary">
    /div>

  /form>

      {% for color, message in get_flashed_messages(with_categories=True) %}
     div class="alert alert-{{color}} alert-dismissible" role="alert">
  button type="button" class="close" data-dismiss="alert" aria-label="Close">span aria-hidden="true">times;/span>/button>
    p>{{message}}/p>
/div>
  {% endfor %}
/body>
/html>