Python 檔案整理腳本按類型整理資料夾內容，預設只預覽、不移動或刪除檔案

Everyone has that one folder. Downloads, Desktop, some project directory — hundreds of files, no structure, and the thought of sorting it by hand is so dull you just... don't.

I wrote a small Python script that does it for you. It sorts a folder's files into subfolders by type, and the important part is in the title: by default, it changes nothing. It only shows you what it would do. You have to explicitly tell it to move files.

What it does

Point it at a folder and it sorts every file into one of six categories:

No dependencies beyond the standard library — just argparse, shutil, and pathlib. No install step at all.

Usage

python file_organizer.py ~/Downloads            # dry run, no changes
python file_organizer.py ~/Downloads --apply    # actually move files

The dry run prints lines like would move: report.pdf -> Documents/ and finishes with a count. Only --apply performs the moves.

How it works

The whole script is built around one mapping and one function:

CATEGORIES = {
    "Images": {".jpg", ".jpeg", ".png", ".gif", ".webp", ".svg"},
    "Documents": {".pdf", ".doc", ".docx", ".txt", ".md"},
    "Spreadsheets": {".csv", ".xls", ".xlsx", ".ods"},
    "Archives": {".zip", ".tar", ".gz", ".rar", ".7z"},
    "Code": {".py", ".js", ".html", ".css", ".json"},
}

def category_for(path):
    """Return the category folder name for a file's extension."""
    for name, extensions in CATEGORIES.items():
        if path.suffix.lower() in extensions:
            return name
    return "Others"

Extensions are lowercased before matching, so Photo.JPG and photo.jpg land in the same folder. Anything unknown falls into Others rather than being skipped silently — a file you can't find is worse than a file in a misc folder.

The organising function keeps the dry-run and apply paths in one place, so they can never drift apart:

def organize(folder, apply=False):
    folder = Path(folder)
    if not folder.is_dir():
        print(f"error: {folder} is not a folder", file=sys.stderr)
        return 1
    moved = 0
    for path in sorted(folder.iterdir()):
        if not path.is_file():
            continue  # never touch subfolders
        target_dir = folder / category_for(path)
        target = target_dir / path.name
        if apply:
            target_dir.mkdir(exist_ok=True)
            shutil.move(str(path), str(target))
            print(f"moved: {path.name} -> {target_dir.name}/")
        else:
            print(f"would move: {path.name} -> {target_dir.name}/")
        moved += 1
    mode = "moved" if apply else "would move (dry run — use --apply to move)"
    print(f"{moved} file(s) {mode}")
    return 0

Three safety decisions are doing the quiet work here:

1. Dry run is the default. The destructive action requires an explicit flag. If you run it by accident, nothing happens — you just get a preview.
2. It never touches subfolders. Only files directly in the folder are moved. Your existing structure stays intact.
3. It never deletes. Files are moved, not removed. If a category looks wrong, everything is still there, one folder away.

Three lessons I'd pass on

1. Make the safe behaviour the default. A script that moves files should have to be talked into it. Dry-run-first is a design decision, not a feature — and it's the reason I'd trust this on a real Downloads folder.
2. Small scripts beat small apps. This is about 70 lines and has no dependencies. It doesn't need a GUI, a config file, or a scheduler to be useful.
3. Print what you're doing. Every move gets a line of output, and the run ends with a count. When a script touches your files, silence is a bug.

This is the second tool in my Python Automation Toolkit — the first scrapes a catalogue into a clean Excel report, and this one tidies the folder that report lands in. Next, I'll write about the project that taught me the most: a RAG-powered assistant that answers questions about Pakistani electricity bills.

Malik Ali Hassan — .NET & full-stack developer, final-year Software Engineering student. I build Python automation, AI assistants, and web apps.