函数参数的使用 练习

# 1、写函数，，用户传入修改的文件名，与要修改的内容，执行函数，完成批了修改操作
'''
import os
def file(file,old,new):
    with open(file,mode='rt',encoding='utf-8') as f1,open('files.txt',mode='wt',encoding='utf-8') as f2:
        for line in f1:
            f2.write(line.replace(old,new))
    os.remove(file)
    os.rename('files.txt',file)
file('db.txt','tank','alice')
'''
# 2、写函数，计算传入字符串中【数字】、【字母】、【空格] 以及 【其他】的个数
'''
l='tank:123: 10007'
def res(strs):
    count1=0
    count2=0
    count3=0
    count4=0
    for i in strs:
        if i.isdigit():
            count1 += 1
        elif i.isalpha():
            count2 += 1
        elif i.isspace():
            count3 += 1
        else:
            count4 += 1
    print(count1,count2,count3,count4)
res(l)
'''
# 3、写函数，判断用户传入的对象（字符串、列表、元组）长度是否大于5。
'''
l='tank:123: 10007'
l1=['tank',123,10007]
l2=('tank',123,10007)
def res(in_put):
    if len(in_put) >= 5:
        print(True)
    else:
        print(False)
res(l)
res(l1)
res(l2)
'''
# 4、写函数，检查传入列表的长度，如果大于2，那么仅保留前两个长度的内容，并将新内容返回给调用者。
'''
l=['tank',123,10007]
def res(lists):
    if len(lists) >= 2:
        lists=lists[0:2]
        print(lists)
res(l)
'''
# 5、写函数，检查获取传入列表或元组对象的所有奇数位索引对应的元素，并将其作为新列表返回给调用者。
'''
l2=('tank',123,10007)
l=[]
def res(cmd):
    cmd=list(cmd)
    for i in range(0,len(cmd)):
        if i % 2 == 1:
            l.append(cmd.pop(i))
    print(l)
res(l2)
'''
# 6、写函数，检查字典的每一个value的长度,如果大于2，那么仅保留前两个长度的内容，并将新内容返回给调用者。
# dic = {"k1": "v1v1", "k2": [11,22,33,44]}
# PS:字典中的value只能是字符串或列表
'''
dic = {"k1": "v1v1", "k2": [11,22,33,44]}
def res(dicts):
    for i in dicts:
        l=dicts[i]
        if len(l) >= 2:
            l=l[0:2]
            print(l)
res(dic)
'''

# 选做题：编写ATM程序实现下述功能，数据来源于文件db.txt
# 1、充值功能：用户输入充值钱数，db.txt中该账号钱数完成修改
# 2、转账功能：用户A向用户B转账1000元，db.txt中完成用户A账号减钱，用户B账号加钱
# 3、提现功能：用户输入提现金额，db.txt中该账号钱数减少
# 4、查询余额功能：输入账号查询余额

# 选做题中的选做题：登录功能
# 用户登录成功后，内存中记录下该状态，上述功能以当前登录状态为准，必须先登录才能操作
dic={}
msg = {'0':'退出','1': '充值','2': '转账','3': '提现','4':'查询余额'}
def users(file,user_input,pas):
    with open(file,mode='rt',encoding='utf-8') as f1:
        for line in f1:
            user,word = line.strip().split(':')
            if user_input == user and pas == word:
                print('登录成功!')
                tag=True
                while tag:
                    with open('db.txt', mode='rt', encoding='utf-8') as f2:
                        for line2 in f2:
                            user2, money = line2.strip().split(':')
                            dic[user2] = int(money)
                    msg = "'0':'退出','1': '充值','2': '转账','3': '提现','4':'查询余额'"
                    print(msg)
                    cmd = input('请输入命令编号>>: ').strip()
                    if not cmd.isdigit():
                        print('必须输入命令编号的数字')
                        continue
                    elif cmd not in msg:
                        print('输入的命令不存在')
                        continue
                    else:
                        if cmd == '0':
                            break
                        elif cmd == '1':
                            incount = input('请输入充值金额：').strip()
                            incount = int(incount)
                            user2=user_input
                            dic[user2] += incount
                            with open('db.txt', mode='wt', encoding='utf-8') as f3:
                                for user2, money in dic.items():
                                    f3.write(f'{user2}:{money}
')
                                continue
                        elif cmd == '2':
                            usernameb=input('请输入对方账户名称：')
                            if usernameb == user_input:
                                print('您不能给自己转账')
                                continue
                            if usernameb not in dic:
                                print('账户不存在')
                                continue
                            else:
                                outcount = input('请输入转账金额：')
                                outcount = int(outcount)
                                user2 = user_input
                                dic[user2] -= outcount
                                user2=usernameb
                                dic[user2] += outcount
                                with open('db.txt', mode='wt', encoding='utf-8') as f3:
                                    for user2, money in dic.items():
                                        f3.write(f'{user2}:{money}
')
                                    continue
                        elif cmd == '3':
                            incount = input('请输入提现金额：').strip()
                            incount = int(incount)
                            user2=user_input
                            dic[user2] -= incount
                            with open('db.txt', mode='wt', encoding='utf-8') as f3:
                                for user2, money in dic.items():
                                    f3.write(f'{user2}:{money}
')
                                continue
                        elif cmd == '4':
                            user2=user_input
                            money=dic[user2]
                            print(money)
            else:
                print('登录失败')
users('dbs.txt','tank','123')