Python 學習筆記（七）Python字元串（四）

輸入輸出

 輸入函數 raw_input (Python3:input)

 1 >>> raw_input("請輸入一個字母") #獲取輸入內容的一個函數
 2 請輸入一個字母A
 3 'A'
 4 >>>
 5 >>> name = raw_input("Please input your name:") #輸入得內容賦值給一個變數
 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)  #通過raw_input 得到的結果是一個字元串類型
16 <type 'str'>
17 >>> help(raw_input) #查看raw_input詳細內容
18 Help on built-in function raw_input in module __builtin__:
19 
20 raw_input(...)
21     raw_input([prompt]) -> string   返回值字元串
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中是一個語句 ，在python3中print() 是一個函數

格式化   指定一種格式，按照某種格式列印出來,

　　　　制定一種模板,在模板中某個地方留出一些空位，在空位上填上某些內容，那麼這些空位就需要一些符號來表示，通常稱之為占位符

%s  字元串占位符

%d  整數占位符

%f  浮點數占位符

 3 >>> "I LIKE %s"
 4 'I LIKE %s'
 5 >>> "I Like %s"%"Python"  #用%之後的Python 來填充%s這個占位符
 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)  #括弧中為字元串和數字
15 tom was born in 2018
16 >>>

用花括弧{}索引值 占位符 Python 推薦使用  {} 

　　 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 '