outgoingMessage.getHeader(name)
name
<string> 标头名称- 返回 <string> | <undefined>
获取具有给定名称的 HTTP 标头的值。
如果消息中不存在这样的名称,则为 undefined
。
name
<string> Name of header- Returns <string> | <undefined>
Gets the value of HTTP header with the given name. If such a name doesn't
exist in message, it will be undefined
.