Office.SharedProperties interface  
Represents the properties of an appointment or message in a shared folder or shared mailbox.
For more information on how this object is used, see Enable shared folders and shared mailbox scenarios in an Outlook add-in.
Remarks
[ API set: Mailbox 1.8 for shared folder support, Mailbox 1.13 for shared mailbox support ]
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Examples
// Link to full sample: https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/outlook/65-delegates-and-shared-folders/get-shared-properties.yaml
Office.context.mailbox.item.getSharedPropertiesAsync((result) => {
  if (result.status === Office.AsyncResultStatus.Failed) {
    console.error("The current folder or mailbox isn't shared.");
    return;
  }
  const sharedProperties = result.value;
  console.log(`Owner: ${sharedProperties.owner}`);
  console.log(`Permissions: ${sharedProperties.delegatePermissions}`);
  console.log(`Target mailbox: ${sharedProperties.targetMailbox}`);
});
Properties
| delegate | The permissions that the delegate has on a shared folder, or the user has on a shared mailbox. | 
| owner | The email address of the owner of a shared item. | 
| target | The location of the owner's mailbox for the delegate's access. This location may differ based on the Outlook client. Use with  Example usage:  | 
| target | The REST API's base URL (currently  Use with  Example usage:  | 
Property Details
		delegatePermissions
	 
	The permissions that the delegate has on a shared folder, or the user has on a shared mailbox.
delegatePermissions: MailboxEnums.DelegatePermissions;Property Value
owner
The email address of the owner of a shared item.
owner: string;Property Value
string
		targetMailbox
	 
	The location of the owner's mailbox for the delegate's access. This location may differ based on the Outlook client.
Use with targetRestUrl to construct the REST operation's URL.
Example usage: targetRestUrl + "/{api_version}/users/" + targetMailbox + "/{REST_operation}"
targetMailbox: string;Property Value
string
		targetRestUrl
	  
	The REST API's base URL (currently https://outlook.office.com/api).
Use with targetMailbox to construct the REST operation's URL.
Example usage: targetRestUrl + "/{api_version}/users/" + targetMailbox + "/{REST_operation}"
targetRestUrl: string;Property Value
string