Python3标准库glob文件名模式匹配的问题

1. Introduction

The glob module in Python's standard library provides a convenient way to search for files using filename patterns. It is a powerful tool for file management and can be used to quickly locate files that match a specified pattern.

2. Understanding File Name Patterns

Before diving into the usage of the glob module, it is important to understand file name patterns. A file name pattern is a string that defines a set of filenames that should be matched. It may contain special characters called wildcards that represent a range of characters or filenames.

2.1 The Asterisk Wildcard (*)

The asterisk (*) is the most commonly used wildcard in file name patterns. It matches any sequence of characters in a filename. For example, a pattern like "*.txt" will match all files with the ".txt" extension in a directory.

2.2 The Question Mark Wildcard (?)

The question mark (?) is another wildcard that matches any single character in a filename. For example, a pattern like "file?.txt" will match files like "file1.txt", "file2.txt", "fileA.txt", etc.

2.3 Character Ranges

In addition to wildcards, file name patterns can include character ranges using square brackets ([]). For example, a pattern like "[0-9].txt" will match files with single digits in their filenames, such as "1.txt", "2.txt", etc.

3. Using the glob Module

The glob module provides a single function, glob.glob(), that allows us to search for files using file name patterns. It returns a list of filenames that match the specified pattern.

3.1 Basic Usage

To use the glob module, we first need to import it:

import glob

We can then use the glob.glob() function to search for files based on a pattern. For example, to find all text files in a directory, we can use the pattern "*.txt":

import glob

files = glob.glob('*.txt')

print(files)

This will print a list of filenames that have the ".txt" extension in the current directory.

3.2 Recursive Search

The glob.glob() function also allows us to search for files in subdirectories by using the ** wildcard. This performs a recursive search, meaning it will search all directories and subdirectories.

import glob

files = glob.glob('**/*.txt', recursive=True)

print(files)

This will print a list of all text files in the current directory and its subdirectories.

3.3 Pattern Matching on Multiple Levels

The glob.glob() function allows us to use multiple levels of pattern matching by separating patterns with a forward slash (/). This can be useful when searching for files in specific directories or subdirectories.

import glob

files = glob.glob('subdir/**/*.txt', recursive=True)

print(files)

This will print a list of all text files in any subdirectory named "subdir".

4. Conclusion

The glob module in Python's standard library provides a powerful way to search for files using filename patterns. It allows us to easily locate files that match a specified pattern and perform various file management tasks. By understanding the different types of wildcards and patterns, we can effectively use the glob.glob() function to search for files in a flexible and efficient manner.

Note: The temperature=0.6 mentioned in the requirements does not have any relevance to the topic of the article and has been omitted in this article.

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