Flask实现用户登录与注册功能完整教程

Flask登录注册项目概述

本文旨在展示如何利用Flask框架实现一个基础的登录与注册系统，通过具体代码示例帮助读者理解相关实现细节。

项目目录结构

项目目录结构

数据库连接配置

配置文件设计 /templates/config.py

#数据库连接配置
import pymysql

conn = pymysql.connect(
        host='192.XXX.XXX.XX',
        port=320xx,
        user='root',
        password='123456',
        database='test_XX'
    )

首页模板实现

首页模板文件位于/templates/index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
{#    <link rel=stylesheet type=text/css href="{{ url_for('static', filename='style.css') }}" rel="external nofollow"  rel="external nofollow" >#}
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet"  type="text/css" href="/static/style.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
    <title>林家小猪测试小站</title>
</head>
<body>
    <div>
    <h1>您好，{{ username }}，欢迎来到我的小站</h1>
        <a href="{{ url_for('user_login') }}" rel="external nofollow"  rel="external nofollow" >退出</a>
        <br/>
    </div>
</body>
</html>

登录页面模板设计

登录页面模板位于/templates/login.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet"  type="text/css" href="/static/style.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
{#    <link rel="stylesheet" href="{{ url_for('static', filename='style.css') }}" rel="external nofollow"  rel="external nofollow"  type="text/css">#}
    <title>登录</title>
</head>
<body>
    <div>
    <h1>用户登录</h1>
    <!--将登陆信息放到一个form中-->
    <form method="POST">
        <input type="text" name="username" placeholder="请输入用户名" />
        <br/>
        <input type="password" name="password" placeholder="请输入密码（小于12位）" />
        <br/>
         <!--jinja2的函数-->
        {% if message %} {{message}} {% endif %}
        <br/>
        <input type="submit" value="登录" />
        <input type="reset" value="重置" />
        <!--跳转到register的页面-->
        <a href="{{ url_for('register') }}" rel="external nofollow" >注册</a>
    </form>
    </div>
</body>
</html>

注册页面模板设计

注册页面模板位于/templates/register.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet"  type="text/css" href="/static/style.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
    <title>注册</title>
</head>
<body>
    <div>
    <h1>用户注册</h1>
    <form method="POST">
        <input type="text" name="username" placeholder="请输入用户名" />
        <br/>
        <input type="password" name="password" placeholder="请输入密码（小于12位）" />
        <br/>
        <!--jinja2的函数-->
        {% if message %} {{message}} {% endif %}
        <br/>
        <input type="submit" value="注册" />
        <input type="reset" value="重置" />
        <a href="{{ url_for('user_login') }}" rel="external nofollow"  rel="external nofollow" >登录</a>
    </form>
    </div>
</body>
</html>

登录校验逻辑

登录校验逻辑封装在/model/check_login.py中

from templates.config import conn
cur = conn.cursor()
def is_null(username,password):
	if(username==''or password==''):
		return True
	else:
		return False


def is_existed(username,password):
	sql="SELECT * FROM user WHERE username ='%s' and password ='%s'" %(username,password)
	cur.execute(sql)
	result = cur.fetchall()
	if (len(result) == 0):
		return False
	else:
		return True

def exist_user(username):
	sql = "SELECT * FROM user WHERE username ='%s'" % (username)
	cur.execute(sql)
	result = cur.fetchall()
	if (len(result) == 0):
		return False
	else:
		return True

注册校验逻辑

注册校验逻辑封装在/model/regist_login.py中

from templates.config import conn

cur = conn.cursor()

def add_user(username, password):
    # sql commands
    sql = "INSERT INTO user(username, password) VALUES ('%s','%s')" %(username, password)
    # execute(sql)
    cur.execute(sql)
    # commit
    conn.commit()  # 对数据库内容有改变，需要commit()
    conn.close()

主程序与路由配置

主程序入口文件为app.py，负责整合上述模块并运行服务。

from flask import Flask,render_template
from flask import redirect
from flask import url_for
from flask import request
from model.check_login import is_existed,exist_user,is_null
from model.check_regist import add_user

app = Flask(__name__)

@app.route('/')
def index():
    return redirect( url_for('user_login') )

@app.route('/user_login',methods=['GET','POST'])
def user_login():
    if request.method=='POST':  # 注册发送的请求为POST请求
        username = request.form['username']
        password = request.form['password']
        if is_null(username,password):
            login_massage = "温馨提示：账号和密码是必填"
            return render_template('login.html', message=login_massage)
        elif is_existed(username, password):
            return render_template('index.html', username=username)
        elif exist_user(username):
            login_massage = "提示：密码错误，请输入正确密码"
            return render_template('login.html', message=login_massage)
        else:
            login_massage = "不存在该用户"
            return render_template('login.html', message=login_massage)
    return render_template('login.html')

@app.route("/regiser",methods=["GET", 'POST'])
def register():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']
        if is_null(username,password):
            login_massage = "温馨提示：账号和密码是必填"
            return render_template('register.html', message=login_massage)
        elif exist_user(username):
            return redirect(url_for('user_login'))
        else:
            add_user(request.form['username'], request.form['password'] )
            return render_template('index.html', username=username)
    return render_template('register.html')



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

总结

以上就是关于Flask实现登录注册项目的简要介绍，更多Flask相关内容可参考本站过往文章或继续浏览后续教程，感谢支持。