登录之后更新导航

用上下文处理器app_context_processor定义函数
1. 获取session中保存的值
2. 返回字典
在父模板中更新导航，插入登录状态判断代码。
1. 注意用{% ... %}表示指令。
2. {{ }}表示变量

完成注销功能。

清除session

跳转

from flask import Flask,render_template,request,redirect,url_for,session
from flask_sqlalchemy import SQLAlchemy
import config

app = Flask(__name__)
app.config.from_object(config)

db=SQLAlchemy(app)

class User(db.Model):
    __tablename__='user'
    id=db.Column(db.Integer,primary_key=True,autoincrement=True)
    username=db.Column(db.String(20),nullable=False)
    password=db.Column(db.String(20),nullable=False)
    nickname=db.Column(db.String(50))

#db.create_all()

#查
#user = User.query.filter(User.username == 'sk').first()
#print(user.id,user.password)

#改
#user = User.query.filter(User.username == 'mis1234').first()
#user.password='888888'
#user.username='sk'
#db.session.commit()
#print(user.id,user.password)

#删
#user = User.query.filter(User.username=='sk').first()
#db.session.delete(user)
#db.session.commit()


#增
#user = User(username='mis1234',password='111111')
#db.session.add(user)
#db.session.commit()

@app.route('/')
def base():
    return  render_template('base.html')

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


@app.route('/register/',methods=['GET','POST'])
def register():
    if request.method=='GET':
        return render_template('register.html')
    else:
        usern = request.form.get('username')
        nickn = request.form.get('nickname')
        passw = request.form.get('password')
        user = User.query.filter(User.username == usern).first()
        if user:
            return 'username existed.'
        else:
            user1 = User(username = usern,password = passw,nickname = nickn)
            db.session.add(user1)
            db.session.commit()
            return redirect(url_for('login'))

@app.route('/login/',methods=['GET','POST'])
def login():
    if request.method=='GET':
        return render_template('login.html')
    else:
        usern = request.form.get('username')
        passw = request.form.get('password')
        user = User.query.filter(User.username == usern).first()
        if user:
            if user.password==passw:
                session['user']=usern
                session.permanent = True
                return redirect(url_for('index'))
            else:
                return 'password error.'
        else:
            return 'username is not existed.'

@app.context_processor
def mycontext():
    usern = session.get('user')
    if usern:
        return {'username':usern}
    else:
        return {}

@app.route('/logout/')
def logout():
    session.clear()
    return redirect(url_for('index'))

@app.route('/question')
def question():
    return render_template('question.html')


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

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>{% block title %}首页{% endblock %}</title>
    <script src="../static/js/base.js"></script>
    <link rel="stylesheet" type="text/css" href="../static/css/base.css">

</head>
<body id="myBody">
{% block head %}{% endblock %}
<div class="a">
    <nav>
        <a href="{{ url_for('index') }}">首页</a>
        <a lass="navi" href="{{ url_for('question') }}">发布问答</a>
        <input type="text" name="search">
        <button type="submit">查找</button>
        <img class="navi" id="on_off" onclick="mySwitch()" src="http://www.runoob.com/images/pic_bulbon.gif " width="20px">
        <div class="navi">
            {% if username %}
                <a href="#">{{ username }}</a>
                <a href="{{ url_for('logout') }}">注销</a>
            {% else %}
                <a href="{{ url_for('login') }}">登录</a>
                <a href="{{ url_for('register') }}">注册</a>
            {% endif %}
        </div>
            <a class="navi" href="">收藏</a>
    </nav>
</div>
{%  block main %}{% endblock %}

</body>
</html>

posted @ 2017-11-24 11:40 088郑淑莹阅读(193) 评论(0) 收藏举报

刷新页面返回顶部

登录之后更新导航

公告