VB.NET Reading Outlook Data From Calendar

I am using this code from another solution on this site:

    'In your project include a reference to Microsoft Outlook x.x Object Library
    'where x.x is your version of Outlook
    Dim objApp As Outlook.Application, _
        objNS As Outlook.NameSpace, _
        objCalendar As Outlook.MAPIFolder, _
        objAppointment As Outlook.AppointmentItem
    Set objApp = CreateObject("Outlook.Application")
    Set objNS = objApp.GetNamespace("MAPI")
    'Change OutlookProfileName to the name of your Outlook profile
    objNS.Logon "OutlookProfielName"
    Set objCalendar = objNS.GetDefaultFolder(olFolderCalendar)
   
    'To access each appointment in the calendar do this
    For Each objAppointment In objCalendar.Items
        'Code to do whatever you want to do with each appointment
>      TempVal = (objAppointment.Subject.ToString).ToString
    Next

However I added the part with the >

The problem is if the calendar has no subject, the program crashes.  Can I fix this?