使用 PyPDF2 更新可填写的 pdf答案

【问题标题】：Update a fillable pdf using PyPDF2使用 PyPDF2 更新可填写的 pdf
【发布时间】：2019-11-17 07:51:23
【问题描述】：

我在更新可填写的 pdf 中的命名字段时遇到问题。我的代码如图：

from PyPDF2 import PdfFileWriter, PdfFileReader

myfile = PdfFileReader("invoice_template.pdf")
first_page = myfile.getPage(0)

writer = PdfFileWriter()

data_dict = {
            'business_name_1': 'Consulting',
            'customer_name': 'company.io',
            'customer_email': 'example@icloud.com'
            }

writer.updatePageFormFieldValues(first_page, fields=data_dict)
writer.addPage(first_page)

with open("newfile.pdf","wb") as new:
    writer.write(new)

我在调用updatePageFormFieldValues() 之前和之后使用myfile.getFormTextFields() 检查了字段字典，它们确实得到了更新。但是，生成的 pdf 中没有任何字段值。不知道我做错了什么。我正在使用的pdf可以在here找到

【问题讨论】：

标签： python pdf pypdf2

【解决方案1】：

通过将 PDF 的 NeedAppearances 值设置为 True 来解决此问题。这可以通过一个函数来完成：

def set_need_appearances_writer(writer: PdfFileWriter):
    # See 12.7.2 and 7.7.2 for more information: http://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/PDF32000_2008.pdf
    try:
        catalog = writer._root_object
        # get the AcroForm tree
        if "/AcroForm" not in catalog:
            writer._root_object.update({
                NameObject("/AcroForm"): IndirectObject(len(writer._objects), 0, writer)
            })

        need_appearances = NameObject("/NeedAppearances")
        writer._root_object["/AcroForm"][need_appearances] = BooleanObject(True)
        # del writer._root_object["/AcroForm"]['NeedAppearances']
        return writer

    except Exception as e:
        print('set_need_appearances_writer() catch : ', repr(e))
        return writer

然后，您可以在writer = PdfFileWriter() 行之后添加set_need_appearances_writer(writer) 行，表单应该会更新！

您可以在此处查看更多信息：https://github.com/mstamy2/PyPDF2/issues/355

固定代码

from PyPDF2 import PdfFileWriter, PdfFileReader
from PyPDF2.generic import BooleanObject, NameObject, IndirectObject

def set_need_appearances_writer(writer: PdfFileWriter):
    # See 12.7.2 and 7.7.2 for more information: http://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/PDF32000_2008.pdf
    try:
        catalog = writer._root_object
        # get the AcroForm tree
        if "/AcroForm" not in catalog:
            writer._root_object.update({
                NameObject("/AcroForm"): IndirectObject(len(writer._objects), 0, writer)
            })

        need_appearances = NameObject("/NeedAppearances")
        writer._root_object["/AcroForm"][need_appearances] = BooleanObject(True)
        # del writer._root_object["/AcroForm"]['NeedAppearances']
        return writer

    except Exception as e:
        print('set_need_appearances_writer() catch : ', repr(e))
        return writer

myfile = PdfFileReader("invoice_template.pdf")
first_page = myfile.getPage(0)

writer = PdfFileWriter()
set_need_appearances_writer(writer)

data_dict = {
            'business_name_1': 'Consulting',
            'customer_name': 'company.io',
            'customer_email': 'example@icloud.com'
            }

writer.updatePageFormFieldValues(first_page, fields=data_dict)
writer.addPage(first_page)

with open("newfile.pdf","wb") as new:
    writer.write(new)

【讨论】：

非常感谢！我绝对不会很快解决这个问题。在遵循您链接的主题后，我遇到了错误并添加了导入 from PyPDF2.generic import BooleanObject, NameObject, IndirectObject。