完成登录功能，用session记住用户名

Posted 2020-10-15 蒋宇翔

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登录功能完成：

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

从`flask`中导入`session`
设置`SECRET_KEY`

操作字典一样操作`session`：增加用户名`session[‘username‘]=`username

function fnLogin() {
    var uSer = document.getElementById("user");
    var pAss = document.getElementById("pass");
    var oError = document.getElementById("error_box");
    oError.innerHTML = "<br>";
    if (uSer.value.length < 6 || uSer.value.length > 20) {
        oError.innerHTML = "请输入6-20位用户名";
        return
    } else if ((uSer.value.charCodeAt(0) >= 48) && (uSer.value.charCodeAt(0) <= 57)) {
        oError.innerHTML = "用户名首字不能是数字";
        return
    } else for (var i = 0; i < uSer.value.length; i++) {
        if ((uSer.value.charCodeAt(i) < 48) || (uSer.value.charCodeAt(i) > 57) && (uSer.value.charCodeAt(i) < 97) || (uSer.value.charCodeAt(i) > 122)) {
            oError.innerHTML = "用户名只能是数字和字母";
            return
        }
    }

    if (pAss.value.length < 6 || pAss.value.length > 20) {
        oError.innerHTML = "请输入6-20位密码";
        return
    }
    // 验证弹框
    window.alert("成功")
}


function fnRegistration() {
    var uSer = document.getElementById("user");
    var pAss = document.getElementById("pass");
    var aGain = document.getElementById("again");
    var oError = document.getElementById("error_box");

    oError.innerHTML = "<br>";

    // 验证用户名
    if (uSer.value.length < 6 || uSer.value.length > 20) {
        oError.innerHTML = "请输入6-20位用户名";
        return
    } else if ((uSer.value.charCodeAt(0) >= 48) && (uSer.value.charCodeAt(0) <= 57)) {
        oError.innerHTML = "用户名首字不能是数字";
        return
    } else for (var i = 0; i < uSer.value.length; i++) {
        if ((uSer.value.charCodeAt(i) < 48) || (uSer.value.charCodeAt(i) > 57) && (uSer.value.charCodeAt(i) < 97) || (uSer.value.charCodeAt(i) > 122)) {
            oError.innerHTML = "用户名只能是数字和字母";
            return
        }
    }

    // 验证密码
    if (pAss.value.length < 6 || pAss.value.length > 20) {
        oError.innerHTML = "请输入6-20位密码";
        return
    }

    // 验证再次输入的密码
    if (aGain.value != pAss.value) {
        oError.innerHTML = "请输入相同的密码";
        return
    }
    // 验证弹框
    window.alert("成功")
}

PY:

from flask import Flask, render_template, url_for, redirect, request
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(20))


db.create_all()


# 增加
# user = User(username=‘tan1997‘,password=‘19961021‘)
# db.session.add(user)
# db.session.commit()

# 查询
# user = User.query.filter(User.username == ‘tan1997‘).first()
# print(user.username,user.password)

# 修改
# user=User.query.filter(User.username == ‘tan1997‘).first()
# user.password=1234567
# db.session.commit()

# 删除
# user=User.query.filter(User.username == ‘tan1997‘).first()
# db.session.delete(user)
# db.session.commit()

@app.route(‘/‘)
def myweb():
    return render_template("denglu.html")


@app.route(‘/login/‘, methods=[‘GET‘, ‘POST‘])
def login():
    if request.method == ‘GET‘:
        return render_template("zhuce.html")
    else:
        username = request.form.get(‘username‘)
        password = request.form.get(‘password‘)
        user = User.query.filter(User.username == username).first()
        if user:
            if user.password == password:
                return redirect(url_for(‘myweb‘))
            else:
                return ‘错误‘
        else:
            return ‘用户不存在‘



@app.route(‘/regist/‘, methods=[‘GET‘, ‘POST‘])
def regist():
    if request.method == ‘GET‘:
        return render_template("zhuce.html")
    else:
        username = request.form.get(‘username‘)
        password = request.form.get(‘password‘)
        nickname = request.form.get(‘nickname‘)
        user = User.query.filter(User.username == username).first()
        if user:
            return ‘用户已存在‘
        else:
            user = User(username=username, password=password, nickname=nickname)
            db.session.add(user)  # 数据库，添加操作
            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)

HTML:

{% extends ‘daohang.html‘ %}

{% block denglutitle %}登陆{% endblock %}
{% block dengluhead %}
    <link rel="stylesheet" type="text/css" href="{{ url_for(‘static‘,filename=‘css/denglu.css‘) }}">
    <script src="{{ url_for(‘static‘,filename=‘js/text.js‘) }}"></script>
{% endblock %}
{% block denglubody %}
   <div id="container">
    <div id="header"><h2 align="center">登录</h2></div>
    <div id="content">
        <form>
            账号：<input type="text" name="user" id="user" placeholder="输入用户名">
            <br>
            密码：<input type="password" name="pass" id="pass" placeholder="输入密码">
            <input type="checkbox" name="c1" id="c1" value="">记住账号
            <br>
            <div id="error_box"><br></div>
            <input type="button" value="登录" onclick="fnLogin()">&nbsp



        </form>
    </div></div>


{% endblock %}

import os
DEBUG = True

SECRET_KEY = os.urandom(24)

DIALECT = ‘mysql‘
DRIVER = ‘mysqldb‘
USERNAME = ‘root‘
PASSWORD = ‘ROOT‘
HOST = ‘127.0.0.1‘
DATABASE = ‘mytest‘


SQLALCHEMY_DATABASE_URI = ‘mysql+pymysql://root:@127.0.0.1:3306/mytest?charset=utf8‘
SQLALCHEMY_TRACK_MODIFICATIONS = False

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