3

我使用了一个 .txt 文件，每一行如下所示：

 1/2/09,902,898.5,905.25,913.25,914.5,914.25,915.5,924.5,926.25,929.25,927.5,926

.txt 文件中可能有 50 行这样的行。

这是我制作的代码：

class PriceProcesseor(object):

    import csv
    import datetime

    def __init__(self, text_file_with_prices):
        self.text_file_with_prices = text_file_with_prices
        self.file_each_date_is_a_list_of_strings = self.__turn_file_into_list()

    def __turn_file_into_list(self):
        self.text_file_with_prices1 = open(self.text_file_with_prices, 'rU')
        self.text_file_with_prices2 = csv.reader(self.text_file_with_prices1)
        return self.text_file_with_prices2

    def file_as_list(self):
        '''Returns the file as a list of strings'''
        self.whole_file_as_list_of_lists = []
        for x in self.file_each_date_is_a_list_of_strings:
            self.whole_file_as_list_of_lists.append(x)
        return self.whole_file_as_list_of_lists

    # Make a method that can return any given line

    def return_line(self,line_number):
        self.line_number = line_number
        return self.file_as_list()[line_number]

    def the_works(self):
        self.the_works_list = []
        for date in self.file_as_list():
            self.mini_list = []
            for item in date:
                if '/' in item:
                    self.date = str(datetime.datetime.strptime(item,'%m/%d/%y'))
                    self.date_munged = self.date.strip('00:00:00')
                    self.date_munged_1 = self.date_munged.strip()
                    self.mini_list.append(self.date_munged_1)
                elif '/' not in item:
                    self.mini_list.append(float(item))
            self.the_works_list.append(self.mini_list)
        return self.the_works_list

但是当我这样做时：

my_file = '/directory1/directory2/the_file.txt'
xyz = PriceProcesseor(my_file)
xyz.the_works()

我收到错误消息：

NameError: global name 'csv' is not defined

做错了什么？

4

2 回答 2

3

将import语句放在类定义之外。

import csv
import datetime

class PriceProcesseor(object):
#etc.

类块创建一个范围。当您在该范围内导入内容时，它们只能在该范围内访问。类范围不能直接访问类的方法，因此他们看不到导入的模块。

于 2013-01-06T03:56:54.453 回答
1

因此，正确的处理方法如下：

import csv
import datetime

class PriceProcesseor(object):


    def __init__(self, text_file_with_prices):
        self.text_file_with_prices = text_file_with_prices
        self.file_each_date_is_a_list_of_strings = self.__turn_file_into_list()

    def __turn_file_into_list(self):
        self.text_file_with_prices1 = open(self.text_file_with_prices, 'rU')
        self.text_file_with_prices2 = csv.reader(self.text_file_with_prices1)
        return self.text_file_with_prices2

    def file_as_list(self):
        '''Returns the file as a list of strings'''
        self.whole_file_as_list_of_lists = []
        for x in self.file_each_date_is_a_list_of_strings:
            self.whole_file_as_list_of_lists.append(x)
        return self.whole_file_as_list_of_lists

    # Make a method that can return any given line

    def return_line(self,line_number):
        self.line_number = line_number
        return self.file_as_list()[line_number]

    def the_works(self):
        self.the_works_list = []
        for date in self.file_as_list():
            self.mini_list = []
            for item in date:
                if '/' in item:
                    self.date = str(datetime.datetime.strptime(item,'%m/%d/%y'))

接下来我将文件保存为 ABC123.py。当我输入 import ABC123 时，一切都会完美运行。

于 2013-01-06T18:04:07.890 回答