InReplyToId

KnownPropertyList.InReplyToId field

包含原始消息的 PidTagInternetMessageId 属性（第 2.739 节）值的值。区域：常规消息属性规范名称：PidTagInReplyToId 替代名称：PR_IN_REPLY_TO_ID、PR_IN_REPLY_TO_ID_A、PR_IN_REPLY_TO_ID_W

public static readonly PidTagPropertyDescriptor InReplyToId;