如何通过Outlook加载项在日历约会顶部显示自定义提示及错误消息？

Great question! You’re spot-on that those gray "working on your request" notifications are baked into Office.js, and you can absolutely leverage the same system to show error messages—this is fully supported, even if it’s a bit easy to miss in the official docs.

Here’s how to implement it step by step:

• Use the Office.context.ui.addStatusAsync API
  This is the official method for creating those top-aligned status notifications in Outlook add-ins. You can define your error message, set the notification type to error, and even control how long it stays visible.

  Here’s a concrete code example for an error message:

  Office.context.ui.addStatusAsync(
    "MyAdd encountered an error processing your XXX request",
    { type: Office.MailboxEnums.NotificationType.Error },
    (asyncResult) => {
      if (asyncResult.status === Office.AsyncResultStatus.Failed) {
        // Handle rare cases where the notification itself fails to load
        console.error(`Failed to show notification: ${asyncResult.error.message}`);
      }
    }
  );
  

• Match the native loading notification style (if needed)
  For reference, the gray "working on your request" bar you’re seeing uses the Informational notification type. If you ever need to trigger that loading state manually, just swap the type:

  { type: Office.MailboxEnums.NotificationType.Informational }
  

• Manually dismiss notifications (optional)
  If you want to clear a notification before it auto-closes (like after resolving an error), you can use the notification ID returned from addStatusAsync with removeStatusAsync:

  Office.context.ui.addStatusAsync(
    "MyAdd is working on your XXX request",
    { type: Office.MailboxEnums.NotificationType.Informational },
    (asyncResult) => {
      const notificationId = asyncResult.value;
      // Later, when ready to clear:
      Office.context.ui.removeStatusAsync(notificationId);
    }
  );
  

The best part? Outlook handles all the styling natively—error notifications will get the appropriate visual treatment (usually a red tint, matching the app’s design system) while maintaining the same top-bar layout as the loading messages you’re familiar with.

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