What is os.sep

Python is cross-platform. On Windows, the path separator of the file is '\', on Linux it is '/'.

In order for the code to run on different platforms, should the path be written '\' or '/'?

If you use os.sep, you don't need to consider this. Os.sep automatically adopts the corresponding delimiter according to the platform you are on.

Examples

A path under Linux, / usr / share / python, then the above os.sep is ‘/’

The next path in windows, C: \ Users \ Public \ Desktop, then the above os.sep is ‘\’.

 data_dir = os.sep.join(['hello', 'world'])   

join( )

join (): join string array. Connect the elements in the string, tuple, and list with the specified characters (separator) to generate a new string

grammar:

'sep'.join(seq)

Parameter Description:

sep: separator. Can be empty

seq: sequence of elements to be connected, string, tuple, dictionary

The above syntax is: use sep as a delimiter to merge all the elements of seq into a new string

Return value: returns a string generated by connecting elements with separator sep

os.path.join()

Syntax: os.path.join (path1 [, path2 [, .........]])

Return value: return after combining multiple paths

Note: Parameters before the first absolute value path will be ignored

#Operation on the sequence (using '' and ':' as delimiters respectively)
 
>>> seq1 = ['hello','good','boy','doiido']
>>> print ' '.join(seq1)
hello good boy doiido
>>> print ':'.join(seq1)
hello:good:boy:doiido
 
 
 #Operating on strings
 
>>> seq2 = "hello good boy doiido"
>>> print ':'.join(seq2)
h:e:l:l:o: :g:o:o:d: :b:o:y: :d:o:i:i:d:o
 
 
 #Operating on tuples
 
>>> seq3 = ('hello','good','boy','doiido')
>>> print ':'.join(seq3)
hello:good:boy:doiido
 
 
 #Operation on the dictionary
 
>>> seq4 = {'hello':1,'good':2,'boy':3,'doiido':4}
>>> print ':'.join(seq4)
boy:good:doiido:hello
 
 
 #Merge directories
 
>>> import os
>>> os.path.join('/hello/','good/boy/','doiido')
'/hello/good/boy/doiido'