python有哪些需要学习的知识？-木庄网络博客

本文摘自php中文网，作者零下一度，侵删。

一、python第一行代码：

1	`1 name =` `"你好，世界"2` `print(name)`

二、变量：

1	`1 name =` `"SunDM12"2 name2 = name3` `print("my name : ",name, name2)4 5 name =` `"wangba"6` `print(name, name2)`

name前后变化，而name2 = name已经将“SunDM12”赋值给了name2，name变化后，name2不再变化

三、交互：

1	`1 username = input("username ： ")2` `print(username)`

input函数：用户可以在界面上显示输入字符，并赋值给了username

1	`1 name = input("name :") 2 age = input("age :") 3 job = input("job :") 4 salary = input("salary :") 5 6 info =` `''' 7 ------ info of %s ------ 8 name : %s 9 age : %s10 job : %s11 salary : %s12 '''%(name, name, age, job, salary)`

在屏幕打印的第一种格式。

%s是字符串；%d是双精度；%f是浮点型

1	`1 info2 =` `'''2 ------- info of {_name} -------3 name : {_name}4 age : {_age}5 job : {_job}6 salary : {_salary}7 '''.format(_name=name,8 _name=name,_age=age,_job=job,_salary=salary)`

在屏幕打印的第二种格式。

1	`1 info3 =` `'''2 ------ info of {0} ------3 name : {0}4 age : {1}5 job : {2}6 salary : {3}7 '''.format(name,age,job,salary)`

在屏幕打印的第三种格式。

四、登陆密码：

1 import getpass 2 3 _username = 'SunDM12' 4 _password = '123456' 5 6 username = input('username :') 7 password = input('password :') 8 print(username,password) 9 10 if _username == username and _password == password11 print("welcome user {name} login...".format(name = username))12 else:13 print("Invalid username or password!")

其中getpass是一个package，提供可移植的面膜输入

1. getpass.getpass()

2. getpass.getuser()

五、猜密码游戏

1	`1 correct_number = 122 guess_number = int(input("guess number:"))3 4` `if` `correct_number == guess_number:5` `print("yes,you got it...")6 elif guess_number >correct_number:7` `print("think smaller...")8` `else:9` `print("think bigeer...")`

其中input函数输入是一个字符，此时要将其强制转换为整型

5.1 while循环

1	`1` `count` `= 02` `while` `True:3` `print("count :",count)4` `count` `=` `count` `+15` `if` `count` `== 1000:6` `break`

其中break表示跳出整个循环

correct_number = 12count = 0while count<3:
    guess_number = int(input("guess number:"))if correct_number == guess_number:print("yes,you got it...")elif guess_number >correct_number:print("think smaller...")else:print("think bigeer...")
    count + = 1else:print("you have tried too many times.")

利用while循环进行设计猜数字游戏

5.2 for循环

1	`1` `for` `i in range(10):2` `print("loop ",i)`

显示1到10

1	`1` `for` `i in range(0,10,2):2` `print("loop :",i)`

2是步长

1 2	`correct_number = 12for i in range(3):` `guess_number = int(input("guess number:"))if` `correct_number == guess_number:print("yes,you got it...")elif guess_number >correct_number:print("think smaller...")else:print("think bigeer...")else:print("you have tried too many times.")`

利用for循环进行猜数字游戏

5.3 continue和break的区别

1	`1` `for` `i in range(10): 2` `if` `i<5: 3` `print("loop",i) 4` `else: 5` `continue` `6` `print("....") 7 8` `for` `i in range(10): 9` `print('-------',i)10` `for` `j in range(10):11` `print(j)12` `if` `j>5:13` `break`