python-day1

输入密码时，如果想要不可见，需要利用getpass 模块中的 getpass方法，即：

# 为什么运行后不直接出来“请输入密码：”？？？ #在运行该文件时，会看到
import getpass
pwd = getpass.getpass('请输入密码：')
print('请输入用户名：')
print(pwd)

sys库使用：

 

import sys
print(sys.argv)  # 获取当前文件的路径，值为['C:/Users/17136/PycharmProjects/zx/day1/var.py']

格式化应用：

name = 'zx'
print('i am %s' % name ) #字符串格式化

PS: 字符串是 %s;整数 %d;浮点数%f

例1：

name = input('username：')
pwd = input('pwd：')
age = int(input('age:'))
print(type(age))
job = input('job:')
salary = input('salary:')

info = '''
------infor of %s-------
name: %s
pwd: %s
age: %d
job: %s
salary: %s
''' %(name, name, pwd, age, job, salary)

print(info)

例2：

info2 = '''
------infor of {_name}-------
name: {_name}
pwd: {_pwd}
age: {_age}
job: {_job}
salary: {_salary}
''' .format(_name = name,
            _pwd = pwd,
            _age = age,
            _job = job,
            _salary = salary)
print(info)

 例3：

info3 = '''
------infor of {0}-------
name: {0}
pwd: {1}
age: {2}
job: {3}
salary: {4}
''' .format(name, pwd, age, job, salary)

 

if...else... 应用：

例1：

name = input('请输出用户名：')
pwd = input('请输入密码：')

if name == 'zx' and pwd == '123':
    print('欢迎, zx！')
else:
    print("用户名和密码错误！")

 例2：

_age = 27
age =int(input('age:'))

if age == _age:
    print('yes,you get it.')
elif age > _age:
    print('think it smaller.')
else:
    print('think it bigger.')

 

while...应用：

例1：

count = 0
while True:
    print(count)
    count = count +1

例2：

_age = 27
count = 0
# while True:
#     if count == 3:
#         break
while count < 3:
    age =int(input('age:'))
    if age == _age:
        print('yes,you get it.')
        break
    elif age > _age:
        print('think it smaller.')
    else:
        print('think it bigger.')
    count += 1

# if count == 3:
else:
    print('you have tried too many times.')

for...应用：

例1：

_age = 27
for i in range(3):
    age = int(input('age:'))
    if age == _age:
        print('yes,you get it.')
        break
    elif age > _age:
        print('think it smaller.')
    else:
        print('think it bigger.')
else:
    print('you have tried too many times.')

例2：

for i in range(10):
    print('loop:', i)

例3：

for i in range(0, 10, 2):
    print('loop:', i)

例4：

for i in range(10):
    print('---------',i)
    for j in range(10):
        print(j)
        if j > 5:
            break

 

 

 

while  +  if  应用：

例1：

_age = 27
count = 0
while count < 3:
    age =int(input('age:'))
    if age == _age:
        print('yes,you get it.')
        break
    elif age > _age:
        print('think it smaller.')
    else:
        print('think it bigger.')
    count += 1
if count == 3:
        answer = input('do you want play again?')
        if answer != 'n':
            count = 0

 

 

 

 

 

参考资料：https://www.cnblogs.com/alex3714/articles/5465198.html

 

count = 0
while True:
    print(count)
    count = count +1