如何在Colab Notebook中自动生成无编号目录？

Great question—long Colab notebooks with nested headings can get messy fast, and a manual TOC is both tedious and error-prone. Unfortunately, Colab doesn’t have a one-click "Insert TOC" feature like Google Docs, but there are two excellent auto-generated solutions that fit your needs perfectly:

1. Use Colab's Built-in Outline Panel (Quickest Option) #

This is the simplest, no-code way to navigate your notebook, and it’s auto-updated as you edit headings. Here’s how to access it:

• If the left sidebar is hidden, click the hamburger menu (☰) at the top-left corner of Colab to reveal it.
• Click the Outline icon (looks like a bulleted list, next to the file explorer icon).
• The panel will instantly populate with all your #, ##, and ### headings, nested correctly to match your structure.
• Click any entry to jump directly to that section—no manual linking required.
• Bonus: The outline updates automatically whenever you add, edit, or delete a heading.

2. Generate an Inline Clickable TOC with Code #

If you want a visible, clickable TOC directly within your notebook (e.g., at the top), you can run a script that scans your notebook’s cells and generates a markdown TOC automatically. This eliminates all manual work and ensures accuracy.

Here’s a reliable script to use:

import json
from IPython.display import Markdown

# Load the notebook's underlying JSON structure (synced by Colab when saved)
with open('/content/notebook.ipynb', 'r') as f:
    notebook_data = json.load(f)

toc_entries = []
for cell in notebook_data['cells']:
    if cell['cell_type'] == 'markdown':
        for line in cell['source']:
            # Detect headings (supports #, ##, ### levels)
            if line.startswith('#'):
                heading_level = line.count('#')
                heading_title = line.strip('# ').strip()
                # Create a URL-friendly slug for linking
                slug = heading_title.lower().replace(' ', '-').replace(':', '').replace('?', '').replace('!', '')
                # Build nested TOC line
                toc_line = f"{'  '*(heading_level-1)}- [{heading_title}](#{slug})"
                toc_entries.append(toc_line)

# Display the generated TOC as clickable markdown
Markdown('\n'.join(toc_entries))

How to use this: #

1. Create a new code cell at the location where you want the TOC to appear (usually the top of the notebook).
2. Paste the code above and run the cell.
3. The output will be a nested, clickable markdown TOC that links directly to each heading.
4. If you update your headings later, just re-run the code to refresh the TOC—no manual edits needed.

Pro tip: #

If you want to convert the dynamic TOC output to a static markdown cell (so it persists without re-running the code), right-click the output and select "Save as Markdown Cell". Just remember to re-run the script if you modify your headings afterward.

内容的提问来源于stack exchange，提问作者stevec