Python错误：AttributeError:“非类型”对象没有“到excel”属性

Question

我正在尝试合并一个目录中的所有文件，并将合并后的文件保存到另一个目录中。 我正在使用Python 3.8。 当我运行代码时，我得到以下带有AttributeError的结果：

c:\test\Upload test\Book1.xlsx
c:\test\Upload test\Book2.xlsx
c:\test\Upload test\Book3.xlsx
Traceback (most recent call last):
File "C:/Python/PythonDev/combine.py", line 104, in <module>
newdf.to_excel(writer,"All")
AttributeError: 'NoneType' object has no attribute 'to_excel'

守则：

import pandas as pd
import globe
filelist = glob.glob(r'c:\test\Upload test\*.xlsx')
file1 = "*.*"
for i in  filelist:
    file2 = pd.read_excel(i)
    file2['FileName'] = i
    file1 = ['newdf']
    newdf = file1.append(file2)
    print (i)
writer = pd.ExcelWriter(r'c:\test\Uploaded\uploadfile.xlsx', engine= 'xlsxwriter')
newdf.to_excel(writer,"All")
writer.save()

Answer 1

追加不会返回任何内容

试着这样做：

import pandas as pd
import glob

raw_files = glob.glob(r'c:\test\Upload test\*.xlsx')

pd_files = pd.DataFrame()

for file in raw_files:
    pd_files.append(pd.read_excel(file))

pd_files.to_excel("c:\test\Uploaded\uploadfile.xlsx")