返回一个MsoEnvelope 对象,该对象代表文档的电子邮件标题。
expression.MailEnvelope
expression 必需。该表达式返回一个 Document 对象。
本示例为活动文档的电子邮件标题设置备注。
Sub HeaderComments()
    ActiveDocument.MailEnvelope.Introduction = _
        "Please review this document and let me know " & _
        "what you think.  I need your input by Friday." & _
        "  Thanks."
End Sub