Python3 fdfgen unicode TypeError

Question

我正在使用Python3.3，并试图使用出色的fgfgen / forge_fdf脚本(谢谢各位，顺便说一句)。

当我尝试运行fdfgen的示例测试时，我返回以下错误。

        safe = utf16.replace('\x00)', '\x00\\)').replace('\x00(', '\x00\\(')
TypeError: expected bytes, bytearray or buffer compatible object

环顾四周，这似乎是python 3处理unicode编码的结果吗？但我不确定。下面是一个执行fdfgen代码的示例，后面是fdfgen代码，提供得非常好。预先谢谢：

>>> from fdfgen import forge_fdf
>>> fields = [('last_name', u'Spencer')]
>>> fdf = forge_fdf('SMBRPython.pdf', fields, [], [], [])

    # -*- coding: utf-8 -*-
"""
Port of the PHP forge_fdf library by Sid Steward
(http://www.pdfhacks.com/forge_fdf/)

Anders Pearson <anders@columbia.edu> at Columbia Center For New Media Teaching
and Learning <http://ccnmtl.columbia.edu/>
"""

__author__ = "Anders Pearson <anders@columbia.edu>"
__credits__ = ("Sébastien Fievet <zyegfryed@gmail.com>,"
               "Brandon Rhodes <brandon@rhodesmill.org>")

import codecs

def smart_encode_str(s):
    """Create a UTF-16 encoded PDF string literal for `s`."""
    utf16 = s.encode('utf_16_be')
    safe = utf16.replace('\x00)', '\x00\\)').replace('\x00(', '\x00\\(')
    return ('%s%s' % (codecs.BOM_UTF16_BE, safe))


def handle_hidden(key, fields_hidden):
    if key in fields_hidden:
        return "/SetF 2"
    else:
        return "/ClrF 2"


def handle_readonly(key, fields_readonly):
    if key in fields_readonly:
        return "/SetFf 1"
    else:
        return "/ClrFf 1"


def handle_data_strings(fdf_data_strings, fields_hidden, fields_readonly):
    for (key, value) in fdf_data_strings:
        if type(value) is bool:
            if value:
                yield "<<\n/V/Yes\n/T (%s)\n%s\n%s\n>>\n" % (
                    smart_encode_str(key),
                    handle_hidden(key, fields_hidden),
                    handle_readonly(key, fields_readonly),
                )
            else:
                yield "<<\n/V/Off\n/T (%s)\n%s\n%s\n>>\n" % (
                    smart_encode_str(key),
                    handle_hidden(key, fields_hidden),
                    handle_readonly(key, fields_readonly),
                )
        else:
            yield "<<\n/V (%s)\n/T (%s)\n%s\n%s\n>>\n" % (
                smart_encode_str(value),
                smart_encode_str(key),
                handle_hidden(key, fields_hidden),
                handle_readonly(key, fields_readonly),
            )


def handle_data_names(fdf_data_names, fields_hidden, fields_readonly):
    for (key, value) in fdf_data_names:
        yield "<<\n/V /%s\n/T (%s)\n%s\n%s\n>>\n" % (
            smart_encode_str(value),
            smart_encode_str(key),
            handle_hidden(key, fields_hidden),
            handle_readonly(key, fields_readonly),
        )


def forge_fdf(pdf_form_url="", fdf_data_strings=[], fdf_data_names=[], fields_hidden=[], fields_readonly=[]):

    """Generates fdf string from fields specified

    pdf_form_url is just the url for the form fdf_data_strings and
    fdf_data_names are arrays of (key,value) tuples for the form fields. FDF
    just requires that string type fields be treated seperately from boolean
    checkboxes, radio buttons etc. so strings go into fdf_data_strings, and
    all the other fields go in fdf_data_names. fields_hidden is a list of
    field names that should be hidden fields_readonly is a list of field names
    that should be readonly

    The result is a string suitable for writing to a .fdf file.

    """
    fdf = ['%FDF-1.2\n%\xe2\xe3\xcf\xd3\r\n']
    fdf.append("1 0 obj\n<<\n/FDF\n")

    fdf.append("<<\n/Fields [\n")
    fdf.append(''.join(handle_data_strings(fdf_data_strings, fields_hidden, fields_readonly)))
    fdf.append(''.join(handle_data_names(fdf_data_names, fields_hidden, fields_readonly)))
    fdf.append("]\n")

    if pdf_form_url:
        fdf.append("/F (" + smart_encode_str(pdf_form_url) + ")\n")

    fdf.append(">>\n")
    fdf.append(">>\nendobj\n")
    fdf.append("trailer\n\n<<\n/Root 1 0 R\n>>\n")
    fdf.append('%%EOF\n\x0a')

    return ''.join(fdf)

Answer 1

编码会产生字节值，但您正在使用字符串值来替换事物。使用Byte文字代替：

safe = utf16.replace(b'\x00)', b'\x00\\)').replace(b'\x00(', b'\x00\\(')
return (b'%s%s' % (codecs.BOM_UTF16_BE, safe))

Answer 2

Fdfgen现在已经移植到Python 3中，主要是通过显式地将所有字符串转换为字节文本，就像Martjin Pieters提到的那样。

Answer 3

在Vista上使用python 3.4.2的fdfgen 0.11.0上，当将fdf数据写入文件时，我最初得到了以下错误：

    fdf_file.write(fdf)
TypeError: must be str, not bytes

我最初也得到了这个，但现在不能复制了：

can't convert 'bytes' object to str implicitly

最后，我要做的唯一改变就是将“二进制”模式添加到文件打开命令中。而不是：

fdf_file=open("testForm.fdf","w")

用这个：

fdf_file=open("testForm.fdf","wb")

所有其他行都与他在fdfgen网站上的例子相同。希望这能帮到别人。