如何在kotlin中发送带有文件附件的自定义电子邮件？

我需要发送一封带有Excel文件附件的自定义电子邮件。我遵循了我在网上找到的一个指南，但不断出现以下错误：

javax.mail.internet.ParseException:应为“；”，在
消息中获取了“charset”
。写入（输出）

我想这可能与我编码文本的方式有关。我不能百分之百确定那部分写得是否正确

import com.amazonaws.auth.BasicAWSCredentials
import java.io.ByteArrayOutputStream
import java.nio.ByteBuffer
import java.util.Properties

import javax.activation.DataHandler
import javax.activation.FileDataSource
import javax.mail.Message
import javax.mail.Session
import javax.mail.internet.InternetAddress
import javax.mail.internet.MimeBodyPart
import javax.mail.internet.MimeMessage
import javax.mail.internet.MimeMultipart
import javax.mail.internet.MimeUtility

import com.amazonaws.regions.Regions
import com.amazonaws.services.simpleemail.AmazonSimpleEmailServiceClientBuilder
import com.amazonaws.services.simpleemail.model.RawMessage
import com.amazonaws.services.simpleemail.model.SendRawEmailRequest
import java.io.File
import java.lang.System.out

.
.
.
.

fun sendEmail(){

        val file = File("test.xlsx")

        try{
            val defaultCharSet = MimeUtility.getDefaultJavaCharset()
            val session = Session.getDefaultInstance(Properties())
            val message = MimeMessage(session)
            message.setSubject(EMAIL_SUBJECT, "UTF-8")
            message.setFrom(InternetAddress(EMAIL_FROM))
            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(EMAIL_TO))

            val msg_body =  MimeMultipart("alternative")
            val wrap =  MimeBodyPart()
            val textPart = MimeBodyPart()
            textPart.setContent(MimeUtility
                .encodeText(EMAIL_TEXT_BODY,defaultCharSet,"B"), "text/plain charset=UTF-8")
            textPart.setHeader("Content-Transfer-Encoding", "base64")

            val htmlPart = MimeBodyPart()
            htmlPart.setContent(MimeUtility
                .encodeText(EMAIL_BODY_HTML,defaultCharSet,"B"),"text/html charset=UTF-8")
            htmlPart.setHeader("Content-Transfer-Encoding", "base64")

            msg_body.addBodyPart(textPart)
            msg_body.addBodyPart(htmlPart)

            wrap.setContent(msg_body)

            val msg = MimeMultipart("mixed")
            message.setContent(msg)
            msg.addBodyPart(wrap)

            val att = MimeBodyPart()
            val fds = FileDataSource(file)
            att.dataHandler = DataHandler(fds)
            att.fileName = fds.name

            msg.addBodyPart(att)

            val client = AmazonSimpleEmailServiceClientBuilder.standard()
                .withRegion(Regions.US_EAST_1).build()

            message.writeTo(out)

            val outputStream = ByteArrayOutputStream()
            message.writeTo(outputStream)
            val rawMessage = RawMessage(ByteBuffer.wrap(outputStream.toByteArray()))

            val rawEmailRequest = SendRawEmailRequest(rawMessage)
            client.sendRawEmail(rawEmailRequest)

            println("Email sent")

        }catch (e: Exception){
            println("Email failed to send with error: ${e.message}")
            println(e.printStackTrace())
        }
    }

---

您的MIME类型语法错误。而且您的代码不必要地复杂。 试试这个：

        val textPart = MimeBodyPart()
        textPart.setText(EMAIL_TEXT_BODY, "utf-8")

        val htmlPart = MimeBodyPart()
        htmlPart.setText(EMAIL_BODY_HTML, "utf-8", "html")

您不需要编码文本或设置内容传输编码头，JavaMail将为您完成所有这些