我正在尝试使用 JavaScript 通过 Google API 发送电子邮件。

我的问题是，当我尝试发送不带附件的简单邮件时，出现以下错误：

'raw' RFC822 有效负载消息字符串或通过 /upload/* URL 需要上传消息`

我的代码

function sendMessage() {
gapi.client.load('gmail', 'v1', function() {
    // Web-safe base64 
    var to = 'someone@someone.nl',
        subject = 'Hello World',
        content = 'send a Gmail.'

    var base64EncodedEmail = btoa(
          "Content-Type:  text/plain; charset=\"UTF-8\"\n" +
          "Content-length: 5000\n" +
          "Content-Transfer-Encoding: message/rfc2822\n" +
          "to: someone@someone.nl\n" +
          "from: \"test\" <test@gmail.com>\n" +
          "subject: Hello world\n\n" +

          "The actual message text goes here"
            ).replace(/\+/g, '-').replace(/\//g, '_');

    var mail= base64EncodedEmail;
    console.log(mail);
    var request = gapi.client.gmail.users.messages.send({
      'userId': "me",
      'message': {
          'raw': mail
        }
    });
    request.execute(function(response){
     console.log(response);
   });
  });        

}