In [8]:

    

>>> 'Hello world 2!' #single quoto


    

    
Out[8]:





'Hello world 2!'

In [9]:

    

>>> 'father\'s friend' # \' is used to escape single quoto


    

    
Out[9]:





"father's friend"

In [10]:

    

>>> "mother's friend" #"" or use double quoto


    

    
Out[10]:





"mother's friend"

In [12]:

    

>>> '"Yes", he said'


    

    
Out[12]:





'"Yes", he said'

In [14]:

    

>>> "\"yes\" he said."


    

    
Out[14]:





'"yes" he said.'

In [15]:

    

>>> '"isn\'t it" she said '


    

    
Out[15]:





'"isn\'t it" she said '

In [16]:

    

>>> print ('"isn\'t it" she said') #区别在于把不要的引号给忽略了


    

    




"isn't it" she said

In [19]:

    

>>> s = 'first line .\nsecond line' #\n means newline


    

In [20]:

    

>>> s #without print \n is included in the output


    

    
Out[20]:





'first line .\nsecond line'

In [21]:

    

>>> print (s) # with print \n produces a new line.


    

    




first line .
second line

In [22]:

    

>>> print ('C:\one\name')


    

    




C:\one
ame

In [26]:

    

>>> print (r'C:\one\name') # r means raw string


    

    




C:\one\name

In [33]:

    

>>> print("""\
weahter: whether condition
     temperature           display temperature
     sun                   display whether if it is a sunny day
""")  #"""\"""  \可以阻止打印的第一行空白


    

    




weahter: whether condition
     temperature           display temperature
     sun                   display whether if it is a sunny day

In [35]:

    

>>> 3*"uni" + "form" #string can be connected by +


    

    
Out[35]:





'uniuniuniform'

In [36]:

    

>>> "Hello" "world" "three" #two or more string are connected to each other


    

    
Out[36]:





'Helloworldthree'

In [37]:

    

>>> s = "hello"
s "world" #variable and string could not connected to each other


    

    




  File "<ipython-input-37-b2c9ebc01c60>", line 2
    s "world"
            ^
SyntaxError: invalid syntax

In [38]:

    

>>> s = "Hello" 
s + "world" # However a variable and string could be connected by using "+"


    

    
Out[38]:





'Helloworld'

In [41]:

    

>>> word  = "Python"
>>> word [0]    #Character in position 0


    

    
Out[41]:





'P'

In [43]:

    

>>> word [-5]  # counting from right by using "-" and negative starts from "-1"


    

    
Out[43]:





'y'

In [44]:

    

>>> word [0:4] # character 0 to character 4, 0 included and 4 excluded


    

    
Out[44]:





'Pyth'

In [45]:

    

>>> word [:2] + word [2:] # n[:i]+n[i:] = n


    

    
Out[45]:





'Python'

In [46]:

    

>>> word [34:] #超出部分也没事


    

    
Out[46]:





''

In [47]:

    

>>> s = "todayswtherisreallygood"
len(s) #len() could display string length


    

    
Out[47]:





23

In [ ]: