在Python中创建一个utf-8 csv文件

Question

我无法在Python中创建utf-8 csv文件.

我正在尝试阅读它的文档,并在示例部分中说:

对于所有其他编码,可以使用以下UnicodeReader和UnicodeWriter类.它们在构造函数中采用额外的编码参数,并确保数据通过编码为UTF-8的真实读取器或编写器:

好.所以我有这个代码:

values = (unicode("Ñ", "utf-8"), unicode("é", "utf-8"))
f = codecs.open('eggs.csv', 'w', encoding="utf-8")
writer = UnicodeWriter(f)
writer.writerow(values)

我一直收到这个错误:

line 159, in writerow
    self.stream.write(data)
  File "/usr/lib/python2.6/codecs.py", line 686, in write
    return self.writer.write(data)
  File "/usr/lib/python2.6/codecs.py", line 351, in write
    data, consumed = self.encode(object, self.errors)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 22: ordinal not in range(128)

有人可以给我一个灯,所以我可以理解我到底做错了什么,因为我在调用UnicodeWriter类之前将所有编码设置在各处？

class UnicodeWriter:
    """
    A CSV writer which will write rows to CSV file "f",
    which is encoded in the given encoding.
    """

    def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
        # Redirect output to a queue
        self.queue = cStringIO.StringIO()
        self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
        self.stream = f
        self.encoder = codecs.getincrementalencoder(encoding)()

    def writerow(self, row):
        self.writer.writerow([s.encode("utf-8") for s in row])
        # Fetch UTF-8 output from the queue ...
        data = self.queue.getvalue()
        data = data.decode("utf-8")
        # ... and reencode it into the target encoding
        data = self.encoder.encode(data)
        # write to the target stream
        self.stream.write(data)
        # empty queue
        self.queue.truncate(0)

    def writerows(self, rows):
        for row in rows:
            self.writerow(row)

Answer 1

你不必使用codecs.open; UnicodeWriter接受Unicode输入并负责将所有内容编码为UTF-8.当您UnicodeWriter写入传递给它的文件句柄时,所有内容都已经采用UTF-8编码(因此它适用于您打开的普通文件open).

通过使用codecs.open,您基本上将您的Unicode对象转换为UTF-8字符串UnicodeWriter,然后尝试再次将这些字符串重新编码为UTF-8,就像这些字符串包含Unicode字符串一样,这显然会失败.