#python counter object

 from collections import *

 import os

 def get_counter():

     '''get the Counter object'''

     return Counter()

 def str_to_list(s):

     '''

     a string covert to list,

     return an empty list if the string equal None

     '''

     if s != None:

         return [x for x in s]

     else:

         return []

 def counter(c, l):

     '''统计列表l中每个单词的出现次数，最后返回一个Counter对象'''

     for word in l:

         c[word] += 1

     return c

 def get_file_str(path):

     '''打开指定的文件，并且把文件中的内容以字符串的形式返回'''

     if os.path.exists(path):

         temp_str = ''

         with open(path, 'r') as pf:

             for line in pf:

                 temp_str += line

             return temp_str

     else:

         print('the file [{}] is not exist!'.format(path))

 def test_str():

     #使用自定义字符串测试

     #统计自定义字符串中每个字符出现的次数

     cnt = get_counter()

     temp_str = 'hello,i\'m Hongten,welcome to my space!'

     temp_list = str_to_list(temp_str)

     cnt = counter(cnt, temp_list)

     print(cnt)

 def test_file():

     '''

     读取一个文件，把文件中的内容转化为字符串

     统计该字符串中每个字符串出现的次数

     '''

     cnt = get_counter()

     temp_path = 'c:\\temp.txt'

     temp_str = get_file_str(temp_path)

     temp_list = str_to_list(temp_str)

     cnt = counter(cnt, temp_list)

     print(cnt)

 def main():

     test_str()

     print('#' * 50)

     test_file()

 if __name__ == '__main__':

     main()