Python基础-用户信息登录注册系统(使用MySQL数据库)

# # 需求： 设计一个程序 要求用户可以实现登录、注册、注销登录等功能

# # 用户的用户名(长度6-20)、密码(长度8-20)、昵称、年龄信息保存到数据库中

# # 维护用户的登录状态，每次只能有一个用户处于登录状态，直到选择注销登录

# # 如果不选择退出系统，该程序应当一直运行

import pymysql
import hashlib
from action import *
import re
# 数据库增加功能
def adduser(username, password, name, age):
    try:
        conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='123456', db='user',
                               charset='gbk')
        cus1 = conn.cursor()
        sql = "insert into tb_user(username,password,name,age) VALUES (%s,%s,%s,%s)"
        res = [username, password, name, age]
        cus1.execute(sql, res)
        conn.commit()
        return True
    except Exception as e:
        print(e)
    finally:
        cus1.close()
        conn.close()
# 数据库查找功能
def finduser(username,password):
    try:
        conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='123456', db='user',
                                   charset='gbk')
        cus1 = conn.cursor()
        sql = "select * from tb_user where username=%s"
        res = [username]
        cus1 = conn.cursor()
        cus1.execute(sql, res)
        psw = cus1.fetchall()
        if psw == ():
            return 0
        elif psw[0][0] == password:
            return 1
        else:
            return 2
    except Exception as e:
        print(e)
    finally:
        cus1.close()
        conn.close()
# 数据库查询登录状态功能
def findstatus(username):
    try:
        conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='123456', db='user',
                                   charset='gbk')
        cus1 = conn.cursor()
        sql = "select status from tb_user where username=%s"
        res = [username]
        cus1 = conn.cursor()
        cus1.execute(sql, res)
        psw = cus1.fetchall()
        if psw[0][0] != 0:
            return 1
        else:
            return 0
    except Exception as e:
        print(e)
    finally:
        cus1.close()
        conn.close()
# 数据库变更登录状态功能
def updatestatus0(username):
    try:
        conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='123456', db='user',
                                   charset='gbk')
        cus1 = conn.cursor()
        sql = "update tb_user set status=0 where username=%s"
        res = [username]
        cus1 = conn.cursor()
        psw = cus1.execute(sql, res)
        conn.commit()
        if psw <= 0:
            return False
        else:
            return True
    except Exception as e:
        print(e)
    finally:
        cus1.close()
        conn.close()
# 数据库变更登录状态功能

def updatestatus1(username):
    try:
        conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='123456', db='user',
                                   charset='gbk')
        cus1 = conn.cursor()
        sql = "update tb_user set status=1 where username=%s"
        res = [username]
        cus1 = conn.cursor()
        psw = cus1.execute(sql, res)
        conn.commit()
        if psw <= 0:
            return False
        else:
            return True
    except Exception as e:
        print(e)
    finally:
        cus1.close()
        conn.close()
# 注册功能
def doregist():
    username = input("请输入用户名：")
    password = input("请输入密码：")
    name = input("请输入昵称：")
    age = input("请输入年龄：")
    result_name = re.compile(r"^[a-zA-Z]\w{8,20}")
    result_password = re.compile(r"^[a-zA-Z]\w{6,20}")
    if result_name.match(username) and result_password.match(password):
        regist(username,password,name,age)
    else:
        print("用户名(8-20)或密码(6-20)不合格")
        doregist()

def regist(username,password,name,age):
    if adduser(username,password,name,age):
        print("注册成功，请登录")
        dologin()
    else:
        print("注册失败")
        welcome()
# 登录功能
def dologin():
    username = input("请输入用户名：")
    password = input("请输入密码：")
    login(username,password)

def login(username,password):
    result = finduser(username,password)
    if result == 0:
        print("用户名不存在")
        welcome()
    elif result == 1:
        check(username)
    else:
        print("密码不对")
        welcome()

# 检查登录状态功能
def check(username):
    if findstatus(username) == 1:
        print("用户已登录")
        welcome()
    else:
        if updatestatus1(username):
            print("登录成功")
            loginsuccess(username)
        else:
            print("登录状态更新失败")

# 登录成功
def loginsuccess(username):
    print("登录成功,",username)
    input("按回车注销登录")
    updatestatus0(username)
    welcome()

# 欢迎界面
def welcome():
    choose = input("请登录或注册（输入登录即登录，输入注册即注册）\r\n")
    if choose != "":
        if choose == "登录":
            dologin()
        else:
            if choose == "注册":
                doregist()
            else:
                welcome()
    else:
        welcome()

# 入口
print("欢迎进入学生信息管理系统")
welcome()

# 下面为数据库的结构