Great question—this is something a lot of Apps Script developers grapple with when working with Google Sheets and Drive. Let’s break down when to use each method, their pros and cons, and how they stack up in terms of performance.

Core Purpose Difference #

First, it’s important to remember the core focus of each service:

• SpreadsheetApp is built exclusively for Google Sheets. It’s designed to let you manipulate spreadsheet content directly—think sheets, ranges, formulas, and spreadsheet-specific settings.
• DriveApp is a general-purpose service for all Google Drive files. It handles file-level operations like sharing, ownership, folder management, and basic file metadata, regardless of the file type.

Pros & Cons of Each Method #

Using SpreadsheetApp.openById(id) #

• Pros:
  • Gives you a Spreadsheet object immediately—no extra steps needed to start editing ranges, adding sheets, or adjusting spreadsheet settings (like time zones with setSpreadsheetTimeZone()).
  • Includes all spreadsheet-specific methods right out the gate, so you don’t have to convert a generic file object first.
  • Automatically handles authorization for spreadsheet operations, so you won’t hit unexpected permission issues if you only need to work with sheet content.
• Cons:
  • It’s strictly for Google Sheets. Pass the ID of a Doc, PDF, or any non-sheet file, and you’ll get an immediate error.

Using DriveApp.getFileById(id) #

• Pros:
  • Works with any Drive file—sheets, docs, images, PDFs, you name it. Perfect if your script handles multiple file types.
  • Grants access to file-level properties SpreadsheetApp doesn’t expose, like checking the file owner with getOwner(), viewing last updated time, or adjusting sharing permissions with setSharing().
• Cons:
  • To edit the spreadsheet content, you have to add an extra step: SpreadsheetApp.open(file) to convert the generic Drive file to a Spreadsheet object.
  • If you only need to work with sheet data, this adds unnecessary code and overhead.

Performance & Efficiency #

• Speed: SpreadsheetApp.openById(id) is slightly faster because it skips the intermediate step of fetching a generic Drive file. For single operations, the difference is negligible, but if your script loops through dozens of spreadsheets, that extra conversion step with DriveApp can add up to noticeable lag.
• API Quotas: Both methods count as one API request each, so there’s no difference in quota usage. Just keep in mind Apps Script has daily limits for API calls regardless of which method you use.
• Authorization: Both require similar scopes for basic operations, but DriveApp may need additional scopes if you’re modifying file permissions or moving files between folders.

When to Choose Which? #

• Go with SpreadsheetApp.openById(id) if:
  • Your script only interacts with Google Sheets content (editing ranges, adding sheets, etc.).
  • You want clean, minimal code without extra conversion steps.
• Opt for DriveApp.getFileById(id) if:
  • You need to manage file-level properties (sharing, ownership, folder placement) alongside spreadsheet edits.
  • Your script works with multiple Drive file types and needs a unified way to fetch files first.

内容的提问来源于stack exchange，提问作者J. Doe