ios - 无法检索额外的 header - Mailcore

Question

对于某些电子邮件，我想发送带有标题的额外数据。就像我想知道电子​​邮件是否已加密。为此，我设置了额外的标题，如下所示。

设置额外的标题

let mailBuilder: MCOMessageBuilder! =  MCOMessageBuilder()
mailBuilder.header.subject = "Subject"
mailBuilder.header.setExtraHeaderValue("yes", forName: "Encrypted")
// set rest of data.  From,TO,CC,Body etc and send email.. // Email sending is working properly. 

检索额外的 header

func fetchRequestKind () -> MCOIMAPMessagesRequestKind {
        let kind = MCOIMAPMessagesRequestKind()
        let headers = kind.union(MCOIMAPMessagesRequestKind.headers)
        let structure = headers.union(MCOIMAPMessagesRequestKind.structure)
        let request = structure.union(MCOIMAPMessagesRequestKind.flags)
        let requestHeader = request.union(MCOIMAPMessagesRequestKind.extraHeaders)
        return requestHeader
    }

 let request = self.fetchRequestKind()

                    let messagesNumbers = MCOIndexSet.init() // range get set here
                    let fetch : MCOIMAPFetchMessagesOperation = self.imapSession.fetchMessagesByNumberOperation(withFolder: "Inbox", requestKind:request, numbers: messagesNumbers)
                    fetch.start({ (error, fetchedMessages, vanishedMessages) in
                        if(error != nil)
                        {
                            failure(error.debugDescription)
                        } else {
                            if let mails = fetchedMessages as? [MCOIMAPMessage] {
                               print("\(mails[0].header.subject) &&& \(mails[0].header.allExtraHeadersNames())")
                        }
                    })

但我没有以这种方式获得额外的标题..
我在这里做错了什么。？任何帮助，将不胜感激。

Answer 1

在开始之前，您必须在 fetch 操作中指定所需的额外 header 。在你的情况下:

fetch.extraHeaders = ["Encrypted"]

然后您可以使用以下方法检索该值:

mails[0].header.extraHeaderValue(forName: "Encrypted")

引用: https://github.com/MailCore/mailcore2/issues/1288