这是我最终使用的代码:

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email import Encoders


SUBJECT = "Email Data"

msg = MIMEMultipart()
msg['Subject'] = SUBJECT 
msg['From'] = self.EMAIL_FROM
msg['To'] = ', '.join(self.EMAIL_TO)

part = MIMEBase('application', "octet-stream")
part.set_payload(open("text.txt", "rb").read())
Encoders.encode_base64(part)
    
part.add_header('Content-Disposition', 'attachment; filename="text.txt"')

msg.attach(part)

server = smtplib.SMTP(self.EMAIL_SERVER)
server.sendmail(self.EMAIL_FROM, self.EMAIL_TO, msg.as_string())

代码与Oli的帖子大致相同。

代码基于二进制文件电子邮件附件问题的帖子。

from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
import smtplib
import mimetypes
import email.mime.application

smtp_ssl_host = 'smtp.gmail.com'  # smtp.mail.yahoo.com
smtp_ssl_port = 465
s = smtplib.SMTP_SSL(smtp_ssl_host, smtp_ssl_port)
s.login(email_user, email_pass)


msg = MIMEMultipart()
msg['Subject'] = 'I have a picture'
msg['From'] = email_user
msg['To'] = email_user

txt = MIMEText('I just bought a new camera.')
msg.attach(txt)

filename = 'introduction-to-algorithms-3rd-edition-sep-2010.pdf' #path to file
fo=open(filename,'rb')
attach = email.mime.application.MIMEApplication(fo.read(),_subtype="pdf")
fo.close()
attach.add_header('Content-Disposition','attachment',filename=filename)
msg.attach(attach)
s.send_message(msg)
s.quit()

为了解释，你可以使用这个链接，它解释得很好 https://medium.com/@sdoshi579/to-send-an-email-along-with-attachment-using-smtp-7852e77623

因为这里有很多关于Python 3的答案，但没有一个说明如何使用Python 3.6中经过彻底检查的电子邮件库，这里是从当前电子邮件示例文档中快速复制+粘贴。 (我略去了一些内容，以去除猜测正确MIME类型之类的多余内容。)

以Python >3.5为目标的现代代码不应该再使用email.message.Message API(包括各种MIMEText、MIMEMultipart、MIMEBase等类)或更老的mimetypes。

from email.message import EmailMessage
import smtplib

msg = EmailMessage()
msg["Subject"] = "Our family reunion"
msg["From"] = "me <sender@example.org>"
msg["To"] = "recipient <victim@example.net>"
# definitely don't mess with the .preamble

msg.set_content("Hello, victim! Look at these pictures")

with open("path/to/attachment.png", "rb") as fp:
    msg.add_attachment(
        fp.read(), maintype="image", subtype="png")

# Notice how smtplib now includes a send_message() method
with smtplib.SMTP("localhost") as s:
    s.send_message(msg)

The modern email.message.EmailMessage API is now quite a bit more versatile and logical than the older version of the library. There are still a few kinks around the presentation in the documentation (it's not obvious how to change the Content-Disposition: of an attachment, for example; and the discussion of the policy module is probably too obscure for most newcomers) and fundamentally, you still need to have some sort of idea of what the MIME structure should look like (though the library now finally takes care of a lot of the nitty-gritty around that). Perhaps see What are the "parts" in a multipart email? for a brief introduction.

Using localhost as your SMTP server obviously only works if you actually have an SMTP server running on your local computer. Properly getting email off your system is a fairly complex separate question. For simple requirements, probably use your existing email account and your provider's email server (search for examples of using port 587 with Google, Yahoo, or whatever you have - what exactly works depends somewhat on the provider; some will only support port 465, or legacy port 25 which is however now by and large impossible to use on public-facing servers because of spam filtering).

下面是我从SoccerPlayer的帖子中找到的内容的组合，下面的链接使我更容易附加一个xlsx文件。在这里找到

file = 'File.xlsx'
username=''
password=''
send_from = ''
send_to = 'recipient1 , recipient2'
Cc = 'recipient'
msg = MIMEMultipart()
msg['From'] = send_from
msg['To'] = send_to
msg['Cc'] = Cc
msg['Date'] = formatdate(localtime = True)
msg['Subject'] = ''
server = smtplib.SMTP('smtp.gmail.com')
port = '587'
fp = open(file, 'rb')
part = MIMEBase('application','vnd.ms-excel')
part.set_payload(fp.read())
fp.close()
encoders.encode_base64(part)
part.add_header('Content-Disposition', 'attachment', filename='Name File Here')
msg.attach(part)
smtp = smtplib.SMTP('smtp.gmail.com')
smtp.ehlo()
smtp.starttls()
smtp.login(username,password)
smtp.sendmail(send_from, send_to.split(',') + msg['Cc'].split(','), msg.as_string())
smtp.quit()

from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText
from email.MIMEImage import MIMEImage
import smtplib

msg = MIMEMultipart()
msg.attach(MIMEText(file("text.txt").read()))
msg.attach(MIMEImage(file("image.png").read()))

# to send
mailer = smtplib.SMTP()
mailer.connect()
mailer.sendmail(from_, to, msg.as_string())
mailer.close()

从这里改编。

python 3的另一种方法(如果有人正在搜索):

import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.base import MIMEBase
from email import encoders

fromaddr = "sender mail address"
toaddr = "receiver mail address"

msg = MIMEMultipart()

msg['From'] = fromaddr
msg['To'] = toaddr
msg['Subject'] = "SUBJECT OF THE EMAIL"

body = "TEXT YOU WANT TO SEND"

msg.attach(MIMEText(body, 'plain'))

filename = "fileName"
attachment = open("path of file", "rb")

part = MIMEBase('application', 'octet-stream')
part.set_payload((attachment).read())
encoders.encode_base64(part)
part.add_header('Content-Disposition', "attachment; filename= %s" % filename)

msg.attach(part)

server = smtplib.SMTP('smtp.gmail.com', 587)
server.starttls()
server.login(fromaddr, "sender mail password")
text = msg.as_string()
server.sendmail(fromaddr, toaddr, text)
server.quit()

确保在你的Gmail帐户上允许“不太安全的应用程序”