输入输出
输入函数 raw_input (Python3:input)
1 >>> raw_input("请输入一个字母") #获取输入内容的一个函数 2 请输入一个字母A 3 'A' 4 >>> 5 >>> name = raw_input("Please input your name:") #输入得内容赋值给一个变量 6 Please input your name:tom 7 >>> name 8 'tom' 9 >>> x =raw_input("how old are you?") 10 how old are you?x =raw_input("how old are you?") 11 >>> x =raw_input("how old are you?") 12 how old are you?22 13 >>> x 14 '22' 15 >>> type(x) #通过raw_input 得到的结果是一个字符串类型 16 <type 'str'> 17 >>> help(raw_input) #查看raw_input详细内容 18 Help on built-in function raw_input in module __builtin__: 19 20 raw_input(...) 21 raw_input([prompt]) -> string 返回值字符串 22 23 Read a string from standard input. The trailing newline is stripped. 24 If the user hits EOF (Unix: Ctl-D, Windows: Ctl-Z+Return), raise EOFError. 25 On Unix, GNU readline is used if enabled. The prompt string, if given, 26 is printed without a trailing newline before reading.
print()格式化
print 在python2中是一个语句 ，在python3中print() 是一个函数
格式化 指定一种格式，按照某种格式打印出来,
制定一种模板,在模板中某个地方留出一些空位，在空位上填上某些内容，那么这些空位就需要一些符号来表示，通常称之为占位符
%s 字符串占位符
%d 整数占位符
%f 浮点数占位符
3 >>> "I LIKE %s" 4 'I LIKE %s' 5 >>> "I Like %s"%"Python" #用%之后的Python 来填充%s这个占位符 6 'I Like Python' 7 >>> a = "I Like %s"12 >>> a %"java" 13 'I Like java' 14 >>> print "%s was born in %d "%("tom",2018) #括号中为字符串和数字 15 tom was born in 2018 16 >>>
用花括号{}索引值 占位符 Python 推荐使用 {}
str.format() 格式化
1 >>> s = "I like {0}" 2 >>> s.format("Python") 3 'I like Python' 4 >>> s2 ="%s was born in %d "%("tom",2018) 5 >>> s2.format("tom",2018) 6 'tom was born in 2018 '