python开发_csv(Comma Separated Values)_逗号分隔值_常用导入导出格式_完整版_博主推荐

#
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'''
    在python中，CSV(Comma Separated Values)，从字面上面理解为：逗号分隔值
    举个例子，如：test_csv = 'one, two, three, 4, 5'
    对于test_csv这个变量来说，他里面就存放着这样的值：逗号分隔的值。这样的形式
    在导入和导出中非常常见，如python(version:3.3.2)的API中所描述的一样：

        The so-called CSV(Comma Separated Values) format is the most
        common import and export for spreadsheets and databases.

    csv模块定义了以下函数：

        csv.reader(csvfile, dialect = 'excel', **fmtparams)
            Retuen a reader object which will iterate over lines
            in the given csvfile.
    A short usage example:
        import csv
        with open('eggs.csv', newline = '') as cf:
            spamreader = csv.reader(cf, delimiter = ' ',  quotechar = '|')
            for row in spamreader:
                print(','.join(row))

        csv.write(csvfile, dialect = 'excel', **fmtparams)
            Return a writer object reaponsible for converting the
            user's data into delimited strings on the given file-like
            object.

    A short usage example:
        import csv
        with open('eggs.csv', 'w', newline = '') as cf:
            spamwrite = csv.writer(cf, delimiter = ' ', quotechar = '|', quoting = csv.QUOTE_MINIMAL)
            spamwriter.writerow(['Spam'] * 5 + ['Baked Beans'])
            spamwriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
'''

一下是我做的demo:

运行效果：

Python 3.3.2 (v3.3.2:d047928ae3f6, May 16 2013, 00:03:43) [MSC v.1600 32 bit (Intel)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> ================================ RESTART ================================
>>>
The path [C:\test] dosen't exist!
Created the path [C:\test]
打开文件:[C:\test\test.csv]
写入数据:['one', 'two', 'three', 'four']
打开文件:[C:\test\test.csv]
读取行:['one,two,three,four']
one,two,three,four
##################################################
打开文件:[C:\test\test.csv]
写入数据:['one', 'two', 'three', 'four']
写入数据:['', '', '']
写入数据:['a', 'b', 'c', 'd']
写入数据:['中国', '美国', '日本', '韩国', '新加坡']
打开文件:[C:\test\test.csv]
读取行:['one,two,three,four']
读取行:['1,2,3']
读取行:['a,b,c,d']
读取行:['中国,美国,日本,韩国,新加坡']
one,two,three,four
1,2,3
a,b,c,d
中国,美国,日本,韩国,新加坡
>>> 

在C:\\test目录下面的情况：

====================================================

代码部分：

====================================================

 #python csv

 #Author : Hongten
 #MailTo : hongtenzone@foxmail.com
 #QQ     : 648719819
 #Blog   : http://www.cnblogs.com/hongten
 #Create : 2013-08-21
 #Version: 1.0

 import os
 import csv

 '''
     在python中，CSV(Comma Separated Values)，从字面上面理解为：逗号分隔值
     举个例子，如：test_csv = 'one, two, three, 4, 5'
     对于test_csv这个变量来说，他里面就存放着这样的值：逗号分隔的值。这样的形式
     在导入和导出中非常常见，如python(version:3.3.2)的API中所描述的一样：

         The so-called CSV(Comma Separated Values) format is the most
         common import and export for spreadsheets and databases.

     csv模块定义了以下函数：

         csv.reader(csvfile, dialect = 'excel', **fmtparams)
             Retuen a reader object which will iterate over lines
             in the given csvfile.
     A short usage example:
         import csv
         with open('eggs.csv', newline = '') as cf:
             spamreader = csv.reader(cf, delimiter = ' ',  quotechar = '|')
             for row in spamreader:
                 print(','.join(row))

         csv.write(csvfile, dialect = 'excel', **fmtparams)
             Return a writer object reaponsible for converting the
             user's data into delimited strings on the given file-like
             object.

     A short usage example:
         import csv
         with open('eggs.csv', 'w', newline = '') as cf:
             spamwrite = csv.writer(cf, delimiter = ' ', quotechar = '|', quoting = csv.QUOTE_MINIMAL)
             spamwriter.writerow(['Spam'] * 5 + ['Baked Beans'])
             spamwriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
 '''

 #global var
 SHOW_LOG = True
 #csv file apth
 CSV_FILE_PATH = ''

 def write_data_2_csv_file(path, data):
     '''把数据写入到csv文件
     这里对要写入的数据进行限制，
     数据格式为一个列表：['one', 'two', 'three', 'four']
     '''
     if SHOW_LOG:
         print('打开文件:[{}]'.format(path))
     with open(path, 'w', newline = '') as cf:
         writer = csv.writer(cf, delimiter = ',', quotechar = '|', quoting = csv.QUOTE_MINIMAL)
         if SHOW_LOG:
             print('写入数据:{}'.format(data))
         writer.writerow(data)

 def write_datas_2_csv_file(path, datas):
     '''把数据写入到csv文件
     这里对要写入的数据进行限制，
     数据格式为一个列表,列表里面的每一个元素都是一个列表：
     [
     ['one', 'two', 'three', 'four'],
     ['1', '2', '3'],
     ['a', 'b', 'c', 'd']
     ]
     '''
     if SHOW_LOG:
         print('打开文件:[{}]'.format(path))
     with open(path, 'w', newline = '') as cf:
         writer = csv.writer(cf, delimiter = ',', quotechar = '|', quoting = csv.QUOTE_MINIMAL)
         for row in datas:
             if SHOW_LOG:
                 print('写入数据:{}'.format(row))
             writer.writerow(row)

 def read_csv_file(path):
     '''读取指定的csv文件，并且把csv文件的内容以字符串的形式返回'''
     if os.path.exists(path):
         if SHOW_LOG:
             print('打开文件:[{}]'.format(path))
         content = ''
         with open(path, newline = '') as cf:
             reader = csv.reader(cf, delimiter = ' ', quotechar = '|')
             try:
                 for row in reader:
                     if SHOW_LOG:
                         print('读取行:{}'.format(row))
                     c = ','.join(row) +'\n'
                     content += c
                 return content[0:-1]
             except csv.Errow as e:
                 sys.exit('file {}, line {} : {}'.format(path, reader.line_num, e))
     else:
         print('不存在文件:[{}]'.format(path))

 def mkdirs(path):
     '''创建多级目录'''
     if os.path.exists(path):
         if SHOW_LOG:
             print('The path [{}] existing!'.format(path))
     else:
         if SHOW_LOG:
             print('The path [{}] dosen\'t exist!'.format(path))
         os.makedirs(path)
         if SHOW_LOG:
             print('Created the path [{}]'.format(path))

 def get_path(absPath):
     '''获取到一个绝对路径的目录，
     如绝对路径：'C:\\test\\test.csv'
     则返回的是'C:\\test'
     '''
     if os.path.exists(absPath):
         if SHOW_LOG:
             print('the path [{}] existing!'.format(absPath))
         return os.path.split(absPath)[0]
     else:
         return os.path.split(absPath)[0]

 def init():
     global SHOW_LOG
     SHOW_LOG = True
     global CSV_FILE_PATH
     CSV_FILE_PATH = 'C:\\test\\test.csv'
     csv_dir = get_path(CSV_FILE_PATH)
     mkdirs(csv_dir)

 def main():
     init()
     data = ['one', 'two', 'three', 'four']
     datas = [
     ['one', 'two', 'three', 'four'],
     ['', '', ''],
     ['a', 'b', 'c', 'd'],
     ['中国', '美国', '日本', '韩国', '新加坡']
     ]
     write_data_2_csv_file(CSV_FILE_PATH, data)
     content = read_csv_file(CSV_FILE_PATH)
     print(content)
     print('#' * 50)
     write_datas_2_csv_file(CSV_FILE_PATH,  datas)
     content = read_csv_file(CSV_FILE_PATH)
     print(content)

 if __name__ == '__main__':
     main()