(1)packaging.py 裡面封裝好方法

import pymysql
import hashlib

class MysqlHelper():
    def __init__(self, host, database, user, password, port=3306,charset='utf8'):
        self.host = host
        self.port = port
        self.database = database
        self.user = user
        self.password = password
        self.charset = charset

    def
 
 connect(self):
        self.conn = pymysql.connect(host=self.host, port=self.port, database=self.database, user=self.user, password=self.password,
                                    charset=self.charset)
        self.cursor = self.conn.cursor()

    def close(self):
        self.cursor.close()
        self.conn.close()

    def
 
 select_one(self, sql, params=[]):
        result = None
        try:
            self.connect()
            self.cursor.execute(sql, params)
            result = self.cursor.fetchone()
            self.close()
        except Exception as e:
            print(e)
        return result

    def select_all
 
(self, sql, params=[]):
        result = ()
        try:
            self.connect()
            self.cursor.execute(sql, params)
            result = self.cursor.fetchall()
            self.close()
        except Exception as e:
            print(e)
        return result

    def __edit(self, sql, params):
        count = 0
        try:
            self.connect()
            count = self.cursor.execute(sql, params)
            self.conn.commit()
            self.close()
        except Exception as e:
            print(e)
        return count

    def insert(self, sql, params=[]):
        return self.__edit(sql, params)

    def update(self, sql, params=[]):
        return self.__edit(sql, params)

    def delete(self, sql, params=[]):
        return self.__edit(sql, params)

    def my_md5(self,pwd):
        my_md5=hashlib.md5()
        my_md5.update(pwd.encode('utf-8'))
        return my_md5.hexdigest()

（2）demo04_使用者登入案例.py 進行呼叫

from packaging import MysqlHelper
import  hashlib

def register():
    name=input('使用者名稱：')
    pwd=input('密碼：')

    helper=MysqlHelper(host='localhost',database='laowang',user='root',password='root')
    ret=helper.insert('insert into t_user(name,pwd) VALUES (%s,%s)',[name,helper.my_md5(pwd)])
    if ret>0:
        print('成功')
    else:
        print('失敗')
def login():
    name = input('使用者名稱：')
    pwd = input('密碼：')

    helper = MysqlHelper(host='localhost', database='laowang', user='root', password='root')
    ret=helper.select_one('select count(*) from t_user where name=%s and ped=%s',[name,helper.my_md5(pwd)])
    if ret[0]>0:
        print('成功')
    else:
        print('失敗')

def main():
    while True:
        choice=input('1、註冊1   2、登入')
        if choice=='1':
            register()
        elif choice=='2':
            login()
if __name__=='__main__':
    main()

附錄-資料庫 t_user