使用os.walk时未使用的对象

Question

I have the code below to list all the files in directory and subdirectory.

def GetListFiles(rootdir,fileextension):
    import os
    testfiles = []
    for root,subfolders,files in os.walk(rootdir):
        for file in files:
            ext = "." + fileextension
            if (os.path.splitext(file)[-1].lower()==ext) and (file!="AssemblyInfo.cs"):
                testfiles.append(os.path.join(root,file))
    return testfiles

In the line for root,subfolders,files in os.walk(rootdir): , the variable, subfolders is not used. If I remove it, it is error

"too many values to unpack (expected 2)"

How can I avoid this?

Answer 1

If you want to use a temporary variable, which is not used anywhere, the convention is to use _ .

for root, _, files in os.walk(rootdir):

Note: Unless you use this is REPL, you can use _ . In REPL, _ holds the result of the last evaluated expression.