完成登录功能，用session记住用户名

 

登录功能完成：

1. js:设置return
2. html:设置
   1. form
   2. input

   3. onclick="return fnLogin()"

3. py:
   1. @app.route设置methods
   2. GET
   3. POST
      1. 读取表单数据
      2. 查询数据库
         1. 用户名密码对：
            1. 记住用户名
            2. 跳转到首页
         2. 用户名密码不对：
            1. 提示相应错误。

session：

1. 从`flask`中导入`session`
2. 设置`SECRET_KEY`
3. 操作字典一样操作`session`：增加用户名`session['username']=`username

 

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

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(20))


db.create_all()
# user=User(username='mis1',password='11111')
# db.session.add(user)
# db.session.commit()

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

@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('base'))
            else:
                return u'password error'
        else:
            return u'password is not existed'



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



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

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

　　

{% extends 'base.html' %}
{% block title %}
    登录
{% endblock %}

{% block head %}

    <link href="{{ url_for('static',filename='css/login.css') }}" rel="stylesheet" type="text/css">
    <script src="{{ url_for('static',filename='js/login.js') }}"></script>
{% endblock %}

{% block main %}

    <div class="login" >

          <h1>登录</h1>
        <form action="{{ url_for('login') }}" method="post">

        <p><input id="umane"type="text" name="username" placeholder="请输入用户名"></p>


        <p><input id="upass"type="password"  name="password" placeholder="请输入密码"></p>

          <div id="error_box"><br></div>
<p class="submit">

    <input  onclick="return myLogin()" type="submit" name="commit" value="登录">
     <input  onclick=window.alert("是否取消登录？") type="submit" name="commit" value="取消">
</p>
            </form>
    </div>

</div>
</body>
{% endblock %}

　　

function myLogin() {
            var oUname = document.getElementById("umane");
            var oError = document.getElementById("error_box");
             var oUpass = document.getElementById("upass");
            oError.innerHTML = "<br>"
     //oUname
        if (oUname.value.length>12 || oUname.value.length<6){
            oError.innerHTML = "name:6-12";
            return false;
         } else if((oUname.value.charCodeAt(0)>=48) && oUname.value.charCodeAt(0)<=57){

            oError.innerHTML = "首字母不能是数字";
            return false;
        }else for(var i=0; i<oUname.value.length;i++)
        {

     if((oUname.value.charCodeAt(i)<48 || oUname.value.charCodeAt(i)>57)&&(oUname.value.charCodeAt(i)<97 || oUname.value.charCodeAt(i)>122 )){
                    oError.innerHTML = "只能包含字母和数字";
                    return false;
                }
            }


            if(upass.value.length>12 || upass.value.length<6){
                oError.innerHTML="password;6-12";
                return false;
            }
            return true;
            window.alert("登陆成功 ！")

        }

　　

import  os
SECRET_KEY = os.urandom(24)
SQLALCHEMY_DATABASE_URI = 'mysql+pymysql://root:@127.0.0.1:3306/mis_db?charset=utf8'
SQLALCHEMY_TRACK_MODIFICATIONS = False