PHP前端开发

编写购物商城(1)

百变鹏仔 1个月前 (02-07) #Python
文章标签 购物商城

作业:购物商城

    商品展示,价格

    买,加入购物车

    付款,钱不够

    具体实现了如下功能:
    1、可购买的商品信息显示
    2、显示购物车内的商品信息、数量、总金额
    3、购物车内的商品数量进行增加、减少和商品的删除
    4、用户余额的充值
    5、用户购买完成进行结账,将最终余额回写到用户文件中。

    一、用户文件说明:

kevin 123 50000sky   123 54000mobi  123 80000

    其中第一列为用户名,第二列为密码,第三列为帐户余额。

    二、流程图如下:

   

import sys,os,getpass,timedef input_handle(s):'''用户输入字符数字转化为数字'''if s.isdigit():    #判断用户输入是否是字符数字        s = int(s)     #是的话就进行转换return sdef framework(user="",init_money='',now_money='',recharge_money='',value=''):'''架构函数,展示用户的基本信息'''os.system("clear")    init_money = int(init_money)    now_money = int(now_money)    recharge_money = int(recharge_money)    message = '''******************************************************************************* [32;1m欢迎来到小猪猪购物商城[0m*******************************************************************************会员:%s	金额:%d	当前余额:%d	充值金额:%d	购物车:%d'''  %(user,init_money,now_money,recharge_money,value)    print(message)def goods_list_show(my_dict):'''商品展示模块,用于展示商品'''local_dict = {}'''对商品列表进行遍历并加上数字编号'''i = 1print("商品列表:")    print("=================================================================================================")    print("%-5s  %-15s  %-10s  %-10s  %-10s" %("编号","商品名称","商品价格(元)","商品总数量(个)","商品剩余数量(个)"))for k in my_dict.keys():        v = my_dict[k]if type(v) == dict:            print("%-5s  %-20s  %-15d  %-18d  %-10d"  %(i,k,v['price'],v['num'],v['sum']))            local_dict[i] = [k,v["price"],v['num'],v['sum']]        i += 1print("=================================================================================================")return local_dictdef cart_goods_show(show_dict):'''显示购物车商品,并加上数字编号'''show_all_sum = 0show_all_num = 0'''对商品列表进行遍历并加上数字编号'''message = ('编号',"商品名称","商品价格(元)","商品总数量(个)","购买数量(个)","购买金额(元)")    print("%-5s 	 %-20s 	 %-10s 	 %-10s 	 %-10s 	 %-10s" %message)for k in show_dict:        v = show_dict[k]if type(v) is dict:            print("%-5s 	 %-10s 	 %-10d 	 %-10d 	 %-10d 	 %-10d" %(k,v[0],v[1],v[2],v[3],v[4]))            show_all_num += v[4]            show_all_num += 1print("请确认你购买的商品,总金额:%d元"%(show_all_sum))return (show_all_sum,show_all_num)def cart_goods_modify(modify_dict,modify_goods_dict):'''购物车商品修改列表'''a_flag = 1while a_flag:        index = input("请输入商品编号|完成修改(q):" %modify_dict[index][2])if len(index) != 0:            index = input_handle(index)if index == "q":breakelif index in modify_dict:            b_flag = 1name = modify_dict[index][0]while b_flag:                num = input("请输入新的商品数量(最大值为%d)|完成修改(q):" %modify_dict[index][2])if len(num) != 0:                    num = input_handle(num)if num == 'q':breakelif num == 0:                        modify_goods_dict[name]['num'] = modify_dict[index][2]                        del modify_dict[index]                        b_flag = 0elif num > 0 and num <= modify_dict[index][2]:                        modify_dict[index][3] = num                        modify_dict[index][4] = modify_dict[index][1] * num                        modify_goods_dict[name]['num'] = modify_dict[index][2] - num                        b_flag = 0else:                        passelse:             passreturn  (modify_dict,modify_goods_dict)def shopping_cart_show(my_cart,my_goods_dict):'''购物车展示'''print("欢迎来到你的购物车".center(80,"#"))    goods_all_sum = 0goods_all_num = 0if my_cart:'''调用购物车商品列表函数,并返回商品总金额和总数量'''(goods_all_sum,goods_all_num) = cart_goods_show(my_cart)        choice = input("请进行如下操作:修改记录(c)|继续购物(!c)")if choice == "c":            (my_shop_cart,my_goods_dict) = cart_goods_modify(my_cart,my_goods_dict)            (goods_all_sum,goods_all_num) = cart_goods_show(my_cart)else:            passelse:        print("您当前的购物车为空".center(80,"#"))    time.sleep(2)return (goods_all_sum,goods_all_num,my_goods_dict)def balance_recharge(recharge_init_balance,recharge_now_balance,recharge_money):    recharge_flag = 1while recharge_flag:        recharge_num = input("请输入充值金额|返回(b)|退出(q):")if len(recharge_num) != 0:            recharge_num = input_handle(recharge_num)if recharge_num == "q":            sys.exit(0)        elif recharge_num == 'b':breakelif type(recharge_flag) is int and recharge_num > 0:            recharge_init_balance += recharge_num            recharge_now_balance += recharge_num            recharge_money += recharge_num            recharge_flag = 0print("充值成功,请查收".center(80,"#"))else:            passreturn (recharge_init_balance,recharge_now_balance,recharge_money)def user_billing(billing_list,my_cart,billing_balance):'''结帐模块'''print("欢迎来到结帐模块".center(80,"#"))if my_cart:'''调用购物车商品列表函数'''cart_goods_show(my_cart)        billing_flag = input("请确认是否商品结算(y|n):")if billing_flag == "y":            billing_file = open("info.txt",'w')for user_info in billing_list:                billing_file.writelines(user_info)            billing_file.close()            sys.exit("结帐成功,您当前余额:%d".center(80,"#") %billing_balance)else:            print("退出结算菜单,继续购物".center(80,"#"))            time.sleep(2)else:        print("您当前的购物车为空,无需结算!")        time.sleep(2)'''主程序开始'''if __name__ == "__main__":    goods_list = {             'iphone6': {'price':6000,'num':10,'sum':10},             'ipad': {'price':3000,'num':20,'sum':20},             'mi4': {'price':2000,'num':43,'sum':43},             'huawei6_plus': {'price':1999,'num':8,'sum':8},            }    i  = 0while i < 3:                                                  #只要用户登录不超过3次就不断循环        username = input("请输入用户名:")        password = input("请输入密码:")        user_file = open("info.txt",'r')        user_list = user_file.readlines()        user_file.close()for user_line in user_list:'''分别获取当前账号、密码和余额信息'''user,passwd,init_balance = user_line.strip('').split()            init_balance = int(init_balance)            now_balance = init_balance            my_goods_sum = 0if user == username and password == passwd:                user_shopping_cart = {}                user_shopping_cart_count = 0recharge_value = 0line_num = user_list.index(user_line)                first_flag = 1while first_flag:'''调用框架函数输出用户信息'''framework(username,init_balance,now_balance,recharge_value,user_shopping_cart_count)                    goods_output_dict = goods_list_show(goods_list)   #输出商品信息                    goods_index = input("请选择菜单:输入商品编号 | 购物车(c) | 余额充值(r) | 结账(b) | 退出(q) :")if len(goods_index) != 0:                        goods_index = input_handle(goods_index)if goods_index == 'q':                        sys.exit(0)                    elif goods_index == 'c':'''调用购物车显示函数,并返回购物车商品总金额'''(my_goods_sum,user_shopping_cart_count,goods_list) = shopping_cart_show(user_shopping_cart,goods_list)                        now_balance = init_balance - my_goods_sumif now_balance < 0:                            print("您的余额不足,请及时充值!")                            time.sleep(2)                    elif goods_index == 'r':                        (init_balance,now_balance,recharge_value) = balance_recharge(init_balance,now_balance,recharge_value)                    elif goods_index == 'b':'''更新用户的余额'''user_list[line_num] = user + ' ' + passwd + ' ' + repr(now_balance) + ''user_billing(user_list,user_shopping_cart,now_balance)                    elif goods_index in goods_output_dict:'''取出goods_index商品列表信息并进行赋值和展示'''(goods_name,goods_price,goods_num) = (goods_output_dict[goods_index][0],goods_output_dict[goods_index][1],goods_output_dict[goods_index][2])                        print('【 编号:%-5d 	 名称:%-15s 	 价格:%-5d(元) 	 数量:%-5d(个)】' % (goods_index, goods_name, goods_price, goods_num))                        second_flag = 1while second_flag:                            buy_num = input('请输入购买商品个数(最大值为%d) | 返回(b) | 退出(q): ' % goods_num)if len(buy_num) != 0:                                buy_num = input_handle(buy_num)if buy_num == 'q':                                sys.exit(0)                            elif buy_num == 'b':breakelif type(buy_num) is int and buy_num > 0 and buy_num <= goods_num:                                my_goods_sum = goods_price * buy_numif my_goods_sum <= now_balance:                                    print('购买商品 %s 总价格为 : %d' % (goods_name, my_goods_sum))                                    add_flag = input("请确认是否加入购物车(y | n):")if add_flag == "y":'''判断购物车不存在该商品'''if goods_index not in user_shopping_cart:                                            user_shopping_cart_count += 1'''购物车商品数量加一'''user_shopping_cart[goods_index] = [goods_name,goods_price,goods_num,buy_num,my_goods_sum]else:                                            user_shopping_cart[goods_index][3] += buy_num                                            user_shopping_cart[goods_index][4] += my_goods_sum                                        now_balance -= my_goods_sum                                        goods_list[goods_name]['num'] -= buy_num                                        second_flag = 0else:breakelse:                                    print("您的余额不足,请充值或重新选择,谢谢!")                                    time.sleep(2)else:                                passelse:                         passelse:if i != 2:                print('用户或密码错误,请重新输入,还有 %d 次机会' % (2 - i))            i += 1else:        sys.exit('用户或密码输入错误超过三次,退出系统,欢迎下次光临')

    上述代码不难,难的是思路,思路很重要,要知道如何一步一步去操作,用的也都是我们常用的知识,其实归根揭底我们写程序,大部分使用的都是字符串,字典,列表的功能。还有一些模块之类的。在写程序的过程中,思路显得尤为重要。知道了思路,就考虑如何使用代码去实现,上面程序中学到了如下知识点;

    1、输出格式对其:print("%-5s %-15s %-10s %-10s %-10s" %("编号","商品名称","商品价格(元)","商品总数量(个)","商品剩余数量(个)")),上面代码能够实现对其格式的功能,让我们输出的字符串格式统一,比如上述代码中,编号左对齐5个字符,商品名称左对齐15个字符等等;

    2、str.center()的使用,如print("欢迎来到你的购物车".center(80,"#"))