文件和文件夹 · 计算机入门

为什么需要它

直觉理解

/                 最上层
└── Users
    └── mia
        ├── Documents
        │   └── cv.docx
        └── Pictures
            ├── beach.jpg
            └── 2024
                └── cat.png

定义

文件 File

A file is a named collection of data kept in storage, such as a photo, a document or a program.

文件是保存在存储里、有名字的一份数据，比如一张照片、一份文档或一个程序。

文件夹 Folder（目录 Directory）

A folder, or directory, is a container that holds files and other folders.

文件夹（也叫目录）是装文件和其他文件夹的容器。

路径 Path

A path is the address of a file or folder: the folders from the top down to it, separated by slashes.

路径是文件或文件夹的地址：从最上层一直到它经过的文件夹，用斜杠隔开。

示例

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folders = ["Users", "mia", "Pictures"]   # change me 改这里
file = "cat.png"
path = ""
for name in folders:
    path = path + "/" + name
path = path + "/" + file
print(path)

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path = "/Users/mia/Documents/school/report.docx"   # change me 改这里
parts = path.split("/")[1:]
depth = 0
for part in parts[:-1]:
    print("  " * depth + part + "/")
    depth = depth + 1
print("  " * depth + parts[-1])

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name = "holiday.mp4"   # change me 改这里
kinds = {"jpg": "a picture", "png": "a picture", "mp3": "sound",
         "mp4": "a video", "txt": "plain text", "pdf": "a document",
         "py": "a Python program"}
extension = name.split(".")[-1]
print(name, "is", kinds.get(extension, "a kind of file this machine doesn't know"))

常见错误

小测验

要点

动手练习

3 道小练习：先想一想，再动手改一改看看结果，最后自己来一次。提交马上告诉你对不对。

1. 想一想找出路径

   这是一台电脑文件夹树的一部分：

   /
   └── home
       └── leo
           ├── games
           │   └── chess.py
           └── music
               └── rain.mp3

   rain.mp3 的路径是什么？

2. 改一改照片挪地方了

   Mia 在 Pictures 里面新建了一个叫 pets 的文件夹，把 cat.png 挪了进去。

   改一改文件夹列表，让机器打印出新的路径：

   /Users/mia/Pictures/pets/cat.png

3. 自己来写出路径

   这是 Ana 的电脑：

   /
   └── Users
       └── ana
           ├── Desktop
           └── Documents
               └── 2025
                   └── taxes.pdf

   写出 taxes.pdf 的完整路径。

本课术语