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”

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。

下面是Python 3.6及更新版本的更新版本，使用Python标准库中经过大修的电子邮件模块的EmailMessage类。

import mimetypes
import os
import smtplib
from email.message import EmailMessage

username = "user@example.com"
password = "password"
smtp_url = "smtp.example.com"
port = 587


def send_mail(subject: str, send_from: str, send_to: str, message: str, directory: str, filename: str):
    # Create the email message
    msg = EmailMessage()
    msg['Subject'] = subject
    msg['From'] = send_from
    msg['To'] = send_to
    # Set email content
    msg.set_content(message)

    path = directory + filename

    if os.path.exists(path):
        ctype, encoding = mimetypes.guess_type(path)
        if ctype is None or encoding is not None:
            # No guess could be made, or the file is encoded (compressed), so
            # use a generic bag-of-bits type.
            ctype = 'application/octet-stream'
        maintype, subtype = ctype.split('/', 1)
        # Add email attachment
        with open(path, 'rb') as fp:
            msg.add_attachment(fp.read(),
                           maintype=maintype,
                           subtype=subtype,
                           filename=filename)

    smtp = smtplib.SMTP(smtp_url, port)
    smtp.starttls() # for using port 587
    smtp.login(username, password)
    smtp.send_message(msg)
    smtp.quit()

你可以在这里找到更多的例子。

下面是Oli为python3编写的修改版本

import smtplib
from pathlib import Path
from email.mime.multipart import MIMEMultipart
from email.mime.base import MIMEBase
from email.mime.text import MIMEText
from email.utils import COMMASPACE, formatdate
from email import encoders


def send_mail(send_from, send_to, subject, message, files=[],
              server="localhost", port=587, username='', password='',
              use_tls=True):
    """Compose and send email with provided info and attachments.

    Args:
        send_from (str): from name
        send_to (list[str]): to name(s)
        subject (str): message title
        message (str): message body
        files (list[str]): list of file paths to be attached to email
        server (str): mail server host name
        port (int): port number
        username (str): server auth username
        password (str): server auth password
        use_tls (bool): use TLS mode
    """
    msg = MIMEMultipart()
    msg['From'] = send_from
    msg['To'] = COMMASPACE.join(send_to)
    msg['Date'] = formatdate(localtime=True)
    msg['Subject'] = subject

    msg.attach(MIMEText(message))

    for path in files:
        part = MIMEBase('application', "octet-stream")
        with open(path, 'rb') as file:
            part.set_payload(file.read())
        encoders.encode_base64(part)
        part.add_header('Content-Disposition',
                        'attachment; filename={}'.format(Path(path).name))
        msg.attach(part)

    smtp = smtplib.SMTP(server, port)
    if use_tls:
        smtp.starttls()
    smtp.login(username, password)
    smtp.sendmail(send_from, send_to, msg.as_string())
    smtp.quit()

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

Gmail版本，使用Python 3.6(请注意，您需要更改Gmail设置，以便能够通过smtp从它发送电子邮件:

import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from email.mime.application import MIMEApplication
from os.path import basename


def send_mail(send_from: str, subject: str, text: str, 
send_to: list, files= None):

    send_to= default_address if not send_to else send_to

    msg = MIMEMultipart()
    msg['From'] = send_from
    msg['To'] = ', '.join(send_to)  
    msg['Subject'] = subject

    msg.attach(MIMEText(text))

    for f in files or []:
        with open(f, "rb") as fil: 
            ext = f.split('.')[-1:]
            attachedfile = MIMEApplication(fil.read(), _subtype = ext)
            attachedfile.add_header(
                'content-disposition', 'attachment', filename=basename(f) )
        msg.attach(attachedfile)


    smtp = smtplib.SMTP(host="smtp.gmail.com", port= 587) 
    smtp.starttls()
    smtp.login(username,password)
    smtp.sendmail(send_from, send_to, msg.as_string())
    smtp.close()

用法:

username = 'my-address@gmail.com'
password = 'top-secret'
default_address = ['my-address2@gmail.com'] 

send_mail(send_from= username,
subject="test",
text="text",
send_to= None,
files= # pass a list with the full filepaths here...
)

要与任何其他电子邮件提供商一起使用，只需更改smtp配置。