python PyPDF2模块合成pdf问题

[hjf12402]

求助各位大神，为何第一段代码能成功，第二段代码得到的是一个内容空白的pdf文件，但是总页数等于两个pdf页数之和。

#利用PyPDF2模块将两个pdf文档合成一个新pdf
import os,PyPDF2

os.chdir(r'C:\Users\hjf\Desktop')

pdfWriter = PyPDF2.PdfFileWriter()

pdf1 = open('test1.pdf','rb')
pdf1Reader = PyPDF2.PdfFileReader(pdf1)
for pageNum in range(pdf1Reader.numPages):
    page=pdf1Reader.getPage(pageNum)
    pdfWriter.addPage(page)

pdf2 = open('test2.pdf','rb')
pdf2Reader = PyPDF2.PdfFileReader(pdf2)
for pageNum in range(pdf2Reader.numPages):
    page=pdf2Reader.getPage(pageNum)
    page.rotateClockwise(180)
    pdfWriter.addPage(page)

pdf3 = open('test3.pdf','wb')
pdfWriter.write(pdf3)

pdf3.close()
pdf1.close()
pdf2.close()

#利用PyPDF2模块将两个pdf文档合成一个新pdf
import os, PyPDF2

os.chdir(r'C:\Users\hjf\Desktop')
with open('test3.pdf', 'wb') as pdf3:
    writer = PyPDF2.PdfFileWriter()
    with open('test1.pdf', 'rb') as pdf1:
        pdf1Reader = PyPDF2.PdfFileReader(pdf1)
        for pageNum in range(pdf1Reader.numPages):
            page = pdf1Reader.getPage(pageNum)
            writer.addPage(page)

    with open('test2.pdf', 'rb') as pdf2:
        pdf2Reader = PyPDF2.PdfFileReader(pdf2)
        for pageNum in range(pdf2Reader.numPages):
            page = pdf2Reader.getPage(pageNum)
            page.rotateClockwise(180)
            writer.addPage(page)

    writer.write(pdf3)

[RuiyuanZHOU]

#利用PyPDF2模块将两个pdf文档合成一个新pdf import os, PyPDF2 os.chdir(r'C:\Temp') pdfWriter = PyPDF2.PdfFileWriter() with open('hb2.pdf', 'wb') as pdf3: with open('1.pdf', 'rb') as pdf1: with open('2.pdf', 'rb') as pdf2: pdf1Reader = PyPDF2.PdfFileReader(pdf1) for pageNum in range(pdf1Reader.numPages): page = pdf1Reader.getPage(pageNum) pdfWriter.addPage(page) pdf2Reader = PyPDF2.PdfFileReader(pdf2) for pageNum in range(pdf2Reader.numPages): page = pdf2Reader.getPage(pageNum) page.rotateClockwise(180) pdfWriter.addPage(page) pdfWriter.write(pdf3) ---------------------------------- with open as 语句在块结束后自动关闭了stream。 pdfWriter.addPage(page)只是将当前pdf页信息加入pdfWriter中，并没有将真正内容写入，所以汪with open as 块结束后，pdf页内容也丢失了。

[hjf12402]

引用 1 楼 yshuise 的回复:

调试看看

小白表示调试也看不太懂。。

[hjf12402]

引用 2 楼 RuiyuanZHOU的回复:

#利用PyPDF2模块将两个pdf文档合成一个新pdf import os, PyPDF2 os.chdir(r'C:\Temp') pdfWriter = PyPDF2.PdfFileWriter() with open('hb2.pdf', 'wb') as pdf3: with open('1.pdf', 'rb') as pdf1: with open('2.pdf', 'rb') as pdf2: pdf1Reader = PyPDF2.PdfFileReader(pdf1) for pageNum in range(pdf1Reader.numPages): page = pdf1Reader.getPage(pageNum) pdfWriter.addPage(page) pdf2Reader = PyPDF2.PdfFileReader(pdf2) for pageNum in range(pdf2Reader.numPages): page = pdf2Reader.getPage(pageNum) page.rotateClockwise(180) pdfWriter.addPage(page) pdfWriter.write(pdf3) ---------------------------------- with open as 语句在块结束后自动关闭了stream。 pdfWriter.addPage(page)只是将当前pdf页信息加入pdfWriter中，并没有将真正内容写入，所以汪with open as 块结束后，pdf页内容也丢失了。

感谢，不太懂stream啥意思，不过大概意思明白了。 是writer里面的内容是类似指针的东西，关闭源文件指针就找不到目标了，是这意思吧。

[yshuise]

调试看看