返回或设置约会、日记条目或定期模式的持续时间（以分钟为单位）。对定期事件，该属性仅对约会有效。Long 类型，可读写。
expression.Duration
expression 必选。该表达式返回 AppointmentItem、RecurrencePattern 或 JournalItem 对象。
本 Visual Basic for Applications 示例使用 CreateItem 创建约会，并用 MeetingStatus 将会议状态设置为“Meeting”，以将其变成同时包含必选和可选与会者的会议要求。
Set myOlApp = CreateObject("Outlook.Application")
Set myitem = myOlApp.CreateItem(olAppointmentItem)
myitem.MeetingStatus = olMeeting
myitem.Subject = "Strategy Meeting"
myitem.Location = "Conference Room B"
myitem.Start = #9/24/1997 1:30:00 PM#
myitem.Duration = 90
Set myRequiredAttendee = myitem.Recipients.Add("Nate Sun")
myRequiredAttendee.Type = olRequired
Set myOptionalAttendee = myitem.Recipients.Add("Kevin Kennedy")
myOptionalAttendee.Type = olOptional
Set myResourceAttendee = myitem.Recipients.Add("Conference Room B")
myResourceAttendee.Type = olResource
myitem.Display如果使用 VBScript，则不创建 Application 对象，而且也不能使用命名常量。本示例说明如何使用 VBScript 执行相同任务。
Set myItem = Application.CreateItem(1)
myItem.MeetingStatus = 1
myItem.Subject = "Strategy Meeting"
myItem.Location = "Conference Room B"
myItem.Start = #9/24/97 1:30:00 PM#
myItem.Duration = 90
Set myRequiredAttendee = myItem.Recipients.Add ("Nate Sun")
myRequiredAttendee.Type = 1
Set myOptionalAttendee = myItem.Recipients.Add ("Kevin Kennedy")
myOptionalAttendee.Type = 2
Set myResourceAttendee = myItem.Recipients.Add("Conference Room B")
myResourceAttendee.Type = 3
myItem.Display