注册登录-简易代码

def signup():
    with open("C:\\Users\\Administrator\\Desktop\\账号密码.txt","r") as f:
        line=f.read()
        line=eval(line)
        flag=False
    while True:
        global username1
        username1 = input("输入注册账号:")
        for i in line:
            if i["username"]==username1:
                print("账号已存在")
                break
        else:
            if username1[0].isalnum():
                if len(username1)  in range(5,12):
                    for i in range(1,len(username1)):
                        if (username1[i].isalnum()) or (username1[i]=="_"):
                            print("账号可以使用")
                            flag=True
                            break
                        else:
                            print("账号由数字、字母、下划线组成")
                            break
                else:
                    print("账号由5到12位数字、字母、下划线组成")
                    break
            else:
                print("数字字母作为账号首位")
                break
        if flag == True:
            break
    while True:
        password1=input("输入注册密码:")
        password2 = input("再次输入注册密码:")
        if password1 != password2:
            print("密码不同")
        else:
            break
    submit=input("输入1提交，输入2取消")
    if int(submit)==1:
        data={}
        data["username"]=username1
        data["password"]=password1
        with open("C:\\Users\\Administrator\\Desktop\\账号密码.txt", "r") as f:
            line = f.readlines()
            list_=eval(line[0])
            list_.append(data)
        with open("C:\\Users\\Administrator\\Desktop\\账号密码.txt", "w") as f:
            f.write(str(list_))
    elif int(submit==2):
        exit(0)
def signin():
    print("请登录")
    flag=True
    while True:
        a = input("输入账号:")
        with open("C:\\Users\\Administrator\\Desktop\\账号密码.txt","r") as f:
            line=f.read()
            line=eval(line)
        for i in line:
            if i["username"] == a:
                flag = False
                break
        if flag == False:
            break
        else:
            print("账号不存在")

    b=input("输入密码:")
    c=int(input("输入1提交"))
    if c==1:
        with open("C:\\Users\\Administrator\\Desktop\\账号密码.txt", "r") as f:
            line = f.read()
            line = eval(line)
            flag=True
            for i in line:
                if i["username"] == a and i["password"]==b:
                    print("已登录")
                    flag=False
                    break
            if flag=="Ture":
                print("密码错误")
    else:
        exit(0)
while True:
    choose=int(input("输入1申请，输入2登录,输入0退出"))
    if choose==1:
        signup()
        signin()
    if choose==2:
        signin()
    if choose==0:
        break