Windows平台Python实现目录新增子文件夹监控及MP4路径提取求助

No worries, the watchdog library works perfectly on Windows for this exact scenario. Let's turn your pseudocode into a working Python script that monitors your target directory, detects new subfolders, and grabs all MP4 file paths inside them.

Step 1: Install Watchdog #

First, make sure you have the library installed. Open a command prompt and run:

pip install watchdog

Step 2: Full Working Code #

Here's a complete script that implements your requirement. I've added comments to explain each part:

import time
import os
import glob
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler

class FolderMonitorHandler(FileSystemEventHandler):
    def __init__(self, watch_folder):
        self.watch_folder = watch_folder

    def on_created(self, event):
        # Only react to new folders (ignore files directly created in the watch folder)
        if event.is_directory:
            # Wait a tiny bit to ensure the folder is fully created (avoids race conditions)
            time.sleep(0.5)
            new_folder_path = event.src_path
            print(f"New subfolder created: {new_folder_path}")

            # Find all MP4 files in the new subfolder
            mp4_files = glob.glob(os.path.join(new_folder_path, "*.mp4"))
            
            if mp4_files:
                print("Found MP4 files:")
                for mp4_path in mp4_files:
                    print(f"- {mp4_path}")
            else:
                print("No MP4 files found in this subfolder.")

if __name__ == "__main__":
    # Set your target watch folder here
    WATCH_FOLDER = "C:/watchfolder"
    
    # Initialize the event handler and observer
    event_handler = FolderMonitorHandler(WATCH_FOLDER)
    observer = Observer()
    observer.schedule(event_handler, path=WATCH_FOLDER, recursive=False)  # Recursive=False means only monitor top level for new folders
    
    # Start the observer
    print(f"Monitoring folder: {WATCH_FOLDER}")
    observer.start()
    
    # Keep the script running until interrupted (Ctrl+C)
    try:
        while True:
            time.sleep(1)
    except KeyboardInterrupt:
        observer.stop()
    observer.join()

Key Details to Note: #

• Recursive Monitoring: The script uses recursive=False because we only care about new folders directly created in C:/watchfolder, not nested subfolders. If you want to monitor nested folders too, change this to True.
• Race Condition Fix: The small time.sleep(0.5) ensures the folder is fully created before we scan it—sometimes Windows takes a split second to finalize folder creation.
• MP4 Detection: We use glob.glob() to easily find all .mp4 files. This is simpler than manually walking the directory for this use case.

How to Use: #

1. Replace "C:/watchfolder" with your actual target directory path.
2. Save the script as folder_monitor.py.
3. Run it from the command prompt: python folder_monitor.py.
4. Leave the script running in the background—it will automatically detect new folders and print their MP4 files as they're added.

内容的提问来源于stack exchange，提问作者Harsh Nagarkar