python中的异常错误处理在指定not to之后吐出错误

Question

我试图阻止这个代码给我一个关于我创建的文件的错误，名为beloved.txt我使用FillNotFoundError：说不给我错误并打印未找到的文件，而是打印消息和错误消息。我该如何解决？

def count_words(Filenames):
    with open(Filenames) as fill_object:
        contentInFill = fill_object.read()

    words = contentInFill.rsplit()
    word_length = len(words)
    print("The file " + Filename + " has " + str(word_length) + " words.")

    try:
        Filenames = open("beloved.txt", mode="rb")
        data = Filenames.read()
        return data
    except FileNotFoundError as err:
        print("Cant find the file name")

Filenames = ["anna.txt", "gatsby.txt", "don_quixote.txt", "beloved.txt", "mockingbird.txt"]
for Filename in Filenames:
    count_words(Filename)

Answer 1

一些提示：

• 除了class名称之外，不要将变量大写。
• 在引用不同的东西时使用不同的变量名称。 （即，当你已经拥有该变量的全局版本以及该变量的本地版本时，不要使用Filenames = open("beloved.txt", mode="rb")，现在你将它重新分配给不同的东西!!这种行为会导致头痛......

然而，该脚本的主要问题是尝试在try语句之外打开一个文件。您可以将代码移动到try:内！当你不使用except FileNotFoundError as err:时，我也不明白err。在这种情况下你应该重写except FileNotFoundError: :)

def count_words(file):
    try:
        with open(file) as fill_object:
            contentInFill = fill_object.read()
        words = contentInFill.rsplit()
        word_length = len(words)
        print("The file " + file + " has " + str(word_length) + " words.")
        with open("beloved.txt", mode="rb") as other_file:
            data = other_file.read()
        return data
    except FileNotFoundError:
        print("Cant find the file name")

filenames = ["anna.txt", "gatsby.txt", "don_quixote.txt", "beloved.txt", "mockingbird.txt"]
for filename in filenames:
    count_words(filename)

我也不明白为什么你从同一个文件读取数据时你的函数return data，不管你输入到函数的file？在所有情况下，您将获得相同的结果...

Answer 2

“with open（Filenames）as fill_objec：”句子会抛出异常。因此，您至少必须将该句子包含在try部分中。在您的代码中，您首先使用单词获取len，然后检查特定文件beloved.txt。这个加倍的代码可以让您进行重复的调查。建议：

def count_words(Filenames):
    try:
        with open(Filenames) as fill_object:
            contentInFill = fill_object.read()
        words = contentInFill.rsplit()
        word_length = len(words)
        print("The file " + Filename + " has " + str(word_length) + " words.")
    except FileNotFoundError as err:
        print("Cant find the file name")