How to: Export a Calendar using Payload Sharing

Microsoft Outlook includes the ability to share calendar information with other users by using an iCalendar (.ics) file attached to a MailItem. The CalendarSharing object is used to both generate the iCalendar file from a folder containing calendar items and to generate the MailItem to which the iCalendar file is attached.

This sample uses the CalendarSharing item to share free/busy information for the next seven days with a single recipient:

1. The sample obtains a Folder object reference for the Calendar default folder for the current user, by using the GetDefaultFolder method of the NameSpace object.

2. It uses the GetCalendarExporter method of the Folder object to create a CalendarSharing object reference for the folder.

3. It then sets the following properties on the CalendarSharing object to restrict the range and level of information exported by the object:

4. • The CalendarDetail property is set to limit the information for each calendar item to free/busy information only.

   • The StartDate and EndDate properties are set to restrict the calendar items included in the file to the next seven days.

   • The RestrictToWorkingHours property is set to restrict the calendar items to those that fall within working hours.

   • The IncludeAttachments property is set to exclude any attachments for calendar items exported by the object.

   • The IncludePrivateDetails property is set to exclude the details of any private calendar items exported by the object.

5. It then calles the ForwardAsICal method of the CalendarSharing object to export the calendar items to an iCalendar file and create a MailItem object with the iCalendar file as an attachment. The olCalendarMailFormatDailySchedule constant of the olCalendarMailFormat enumeration is used with the ForwardAsICal method to indicate that the body of the MailItem should contain, in HTML format, free/busy information for the next seven days.

6. Finally, the Add method for the Recipients collection of the newly created MailItem object is called to add the specified recipient and the Send method is used to send the MailItem.

Public Sub ShareWorkCalendarByPayload() 
 
 Dim oNamespace As NameSpace 
 Dim oFolder As Folder 
 Dim oCalendarSharing As CalendarSharing 
 Dim oMailItem As MailItem 
 
 On Error GoTo ErrRoutine 
 ' Get a reference to the Calendar default folder 
 Set oNamespace = Application.GetNamespace("MAPI") 
 Set oFolder = oNamespace.GetDefaultFolder(olFolderCalendar) 
 
 ' Get a reference to a CalendarSharing object for that 
 ' folder. 
 Set oCalendarSharing = oFolder.GetCalendarExporter 
 
 ' Set the CalendarSharing object to restrict 
 ' the information shared in the iCalendar file. 
 With oCalendarSharing 
 ' Send free/busy information only. 
 .CalendarDetail = olFreeBusyOnly 
 
 ' Send information for the next seven days. 
 .startDate = Now 
 .endDate = DateAdd("d", 7, Now) 
 
 ' Restrict information to working hours only. 
 .RestrictToWorkingHours = True 
 
 ' Exclude attachments and private information. 
 .IncludeAttachments = False 
 .IncludePrivateDetails = False 
 End With 
 
 ' Get the mail item containing the iCalendar file 
 ' and calendar information. 
 Set oMailItem = oCalendarSharing.ForwardAsICal( _ 
 olCalendarMailFormatDailySchedule) 
 
 ' Send the mail item to the specified recipient. 
 With oMailItem 
 .Recipients.Add "someone@example.com" 
 .Send 
 End With 
 
EndRoutine: 
 On Error GoTo 0 
 Set oMailItem = Nothing 
 Set oCalendarSharing = Nothing 
 Set oFolder = Nothing 
 Set oNamespace = Nothing 
Exit Sub 
 
ErrRoutine: 
 Select Case Err.Number 
 Case 287 ' &H0000011F 
 ' The user denied access to the Address Book. 
 ' This error occurs if the code is run by an 
 ' untrusted application, and the user chose not to 
 ' allow access. 
 MsgBox "Access to Outlook was denied by the user.", _ 
 vbOKOnly, _ 
 Err.Number & " - " & Err.Source 
 Case -2147467259 ' &H80004005 
 ' Export failed. 
 ' This error typically occurs if the CalendarSharing 
 ' method cannot export the calendar information because 
 ' of conflicting property settings. 
 MsgBox Err.Description, _ 
 vbOKOnly, _ 
 Err.Number & " - " & Err.Source 
 Case -2147221233 ' &H8004010F 
 ' Operation failed. 
 ' This error typically occurs if the GetCalendarExporter method 
 ' is called on a folder that doesn't contain calendar items. 
 MsgBox Err.Description, _ 
 vbOKOnly, _ 
 Err.Number & " - " & Err.Source 
 Case Else 
 ' Any other error that may occur. 
 MsgBox Err.Description, _ 
 vbOKOnly, _ 
 Err.Number & " - " & Err.Source 
 End Select 
 
 GoTo EndRoutine 
End Sub