Absolutely! Microsoft has got you covered with several practical options to build that "Open in Desktop App" functionality into your SaaS product. Let’s break down the most reliable approaches:

1. Office URI Schemes (Quick, No Auth Needed) #

This is the simplest method—you can use dedicated URI protocols that directly trigger the local Office app to pull and open your document. Each Office app has its own unique scheme:

• Word: ms-word:ofe|u|
• Excel: ms-excel:ofe|u|
• PowerPoint: ms-powerpoint:ofe|u|

Example Implementation #

Just construct a link that prepends the scheme to your document’s public HTTPS URL:

<a href="ms-word:ofe|u|https://your-saas-platform.com/files/your-document.docx">Open in Word Desktop App</a>

Key Notes #

• Works as long as the user has the desktop Office suite installed locally.
• Your document URL must use HTTPS (Office enforces this for security reasons).
• If the user doesn’t have the app installed, clicking the link will typically redirect them to the Office download page—adding a fallback message (like "Use web version instead") is a good idea here.

2. Microsoft Graph API (For Microsoft 365-Integrated SaaS) #

If your product already integrates with Microsoft 365 (i.e., users sign in with their Microsoft accounts), the Graph API lets you generate deep links that seamlessly open documents in the desktop app.

How It Works #

1. Fetch the document’s webUrl via the Graph API (from the driveItem resource for files stored in OneDrive/SharePoint).
2. Append query parameters to force opening in the desktop app:
   • For edit mode: &action=edit&mobileredirect=false
   • For view mode: &action=view&mobileredirect=false

Alternatively, use the createLink endpoint to generate a pre-configured link:

POST /me/drive/items/{item-id}/createLink
Content-Type: application/json

{
  "type": "edit",
  "scope": "organization"
}

Modify the returned link.webUrl with the above parameters to trigger the desktop app.

Key Notes #

• Requires user authentication via OAuth 2.0 with Microsoft 365.
• Delivers a more integrated experience, especially if your SaaS syncs with OneDrive/SharePoint.

3. Office JavaScript API (For Web-Embedded Editing) #

If you’re already embedding Office Web Apps (OWA) in your SaaS to let users edit documents in the browser, you can use the Office JS API to add a button that switches to the desktop app.

Example Code Snippet #

// Trigger this function when the user clicks your "Open in Desktop" button
function openInDesktopApp() {
  Office.context.document.openInDesktopClient()
    .then(() => {
      console.log("Successfully opened in desktop app");
    })
    .catch((error) => {
      console.error("Error launching desktop app:", error);
    });
}

Key Notes #

• Only works if the document is already loaded in the Office Web App within your SaaS.
• Requires including the Office JS library in your web page.

General Tips #

• Browser Support: Most modern browsers (Chrome, Edge, Firefox) support Office URI schemes, but test across your target browsers—some may prompt users to allow external app access.
• Error Handling: Always add fallback behavior (like a link to the web version of the document) in case the desktop app can’t be launched.
• Security: Use short-lived signed URLs for private documents to prevent unauthorized access.

内容的提问来源于stack exchange，提问作者Jay