代码中断迭代 - 仅打印第一项

Question

I have folders in a directory named 2001,2002,2003,2004,2005. However when I iterate through them inside the 'for batch in batchno: print(batch)' It only prints the first one 2001. If I print the parameter "Batchno", it gives me all folders. IS there something breaking out of the loop that I am missing? I read that a return can break out of your loop, not sure if "return filename" is doing that.

def getCOAFilePaths(batchno, pdkey):

    for date in pdkey:
        date = date

    for batch in batchno:
        print(batch)
        filepath = f'\\\test/User/000/000/{date}/IMGCD/{batch}/'
        abspth = os.path.abspath(filepath)
        for row in os.listdir(filepath):
            print(abspth+"\\"+row)
            logging.info(abspth+"\\"+row)

        return filepath

    makePdf(filepath, r'C:\Users\TEST\COA\misc.fof')


def makePdf(filepath, SaveToDir):

    os.chdir(filepath)
    try:
        for j in os.listdir(os.getcwd()):
           os.chdir(filepath)
           fname, fext= os.path.splitext(j)
           newfilename = fname + ".pdf"
           im = Image.open(fname + fext)
           os.chdir(SaveToDir)
           im.save(newfilename, "PDF", resolution=100.0)
    except Image.UnidentifiedImageError:
            print(f"{fname+fext} found. Skipping UnidentifiedImageError error because this library cannot open a  .db file "
            f"and convert it to pdf.")


    makePdf(filepath, r'C:\Users\TEST\COA\misc.fof')
    filepath = getCOAFilePaths(x1, x5)

output:

 2001

expected output:

2001,2002,2003,2004,2005

Answer 1

Absolutely! It's hitting your return at the end of the first iteration of the for loop

If I'm interpreting what you're attempting to do correctly, you can simply remove the return and your code should run fine

Answer 2

Yes, a return will end execution of a loop. Try accumulating your result values and return them together after the for has completed.

Example using a list to accumulate the values

filepaths = [] # Create an empty list
for batch in batchno:
    print(batch)
    filepath = f'\\\test/User/000/000/{date}/IMGCD/{batch}/'
    abspth = os.path.abspath(filepath)
    for row in os.listdir(filepath):
        print(abspth+"\\"+row)
        logging.info(abspth+"\\"+row)

    filepaths.append(filepath) # Accumulate values here

return filepaths # Return the list once completed the loop

Edit:

In case you only need those values to call the makePdf function you can also directly call the function inside the loop, without returning anything

for batch in batchno:
    print(batch)
    filepath = f'\\\test/User/000/000/{date}/IMGCD/{batch}/'
    abspth = os.path.abspath(filepath)
    for row in os.listdir(filepath):
        print(abspth+"\\"+row)
        logging.info(abspth+"\\"+row)

    makePdf(filepath, r'C:\Users\TEST\COA\misc.fof')

Answer 3

您在 for 循环中使用了“return”，以便在第一次迭代结束时它将从函数中出来