AttributeError: 'list' object 没有属性 'encode'。 我如何通过 Excel 发送 Email？ Python

Question

So I'm trying to send an e-mail from Excel with Python. Right now I just have all the e-mails set up in column A1 separated by semicolons. If I put the e-mails into Python directly, they send out but when I use the Python call-out, it freaks out giving me this error. How exactly can I make this work?

import smtplib
from email.mime.image import MIMEImage
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
import pandas
from datetime import datetime

server = smtplib.SMTP('relay.xxx.com')
email_df = pandas.read_excel(f"E-mails.xlsx", sheet_name="Emails", nrows=1, usecols = "A")
sender = 'email@email.com'

receivers = 'Email'
receivers = list(email_df)

print(receivers)
msg = MIMEMultipart('related')

msg['Subject'] = 'Test mail'
msg['From'] = sender

with smtplib.SMTP('relay.xxx.com') as server:
    msg['To'] = receivers
    server.sendmail(sender, receivers, bytes(msg.as_string()))
    print(f"Successfully sent email to: {receivers}")

I don't want multiple e-mails to be sent out. I want 1 single e-mail with a bunch of e-mails in the address box.

Alternatively, if there's a way can read it by column, (addr1 in a1, addr in a2) that'd also be better.

Appreciate it.

Answer 1

If you can get your email addresses (from your df) into a list in the desired format, eg:

print(receivers)    
['email1@email1.com', 'email2@email2.com', 'email3@email3.com']

then you can add this after its assignment to turn it into a string for send_mail (as it requires a string instead of a list):

receivers = ", ".join(receivers)

You mention that it would be ideal if you had an email address per row under column A in your spreadsheet. So if you can get your Excel spreadsheet into this format (with a column heading of "Email") then you can do this to get the aforementioned list:

email_df = pandas.read_excel(f"E-mails.xlsx", sheet_name="Emails", usecols = "A")
receivers = email_df['Email'].tolist()

So, for completeness (with Excel spreadsheet in its new format of one email address per row under column A), your code would change to:

import smtplib
from email.mime.image import MIMEImage
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
import pandas
from datetime import datetime

server = smtplib.SMTP('relay.xxx.com')

email_df = pandas.read_excel(f"E-mails.xlsx", sheet_name="Emails")
receivers = email_df['Email'].tolist()

print(receivers)  # Check list is one valid email address per element

receivers = ", ".join(receivers)

sender = 'email@email.com'
msg = MIMEMultipart('related')

msg['Subject'] = 'Test mail'
msg['From'] = sender

with smtplib.SMTP('relay.xxx.com') as server:
    msg['To'] = receivers
    server.sendmail(sender, receivers, bytes(msg.as_string(), encoding='utf-8'))
    print(f"Successfully sent email to: {receivers}")

Answer 2

If you build a message, you'd better use the send_message interface. And I would suggest to use the newer EmailMessage interface which is cleaner and simpler that the older MimeMultipart one:

import smtplib
from email.message import EmailMessage

...
msg = EmailMessage()

msg['Subject'] = 'Test mail'
msg['From'] = sender

msg.set_payload('Message text.\nLine 2...')
# or eventually add parts with msg.add_related(...), msg.add_alternative(..)
#  or msg.add_attachment(...)


with smtplib.SMTP('relay.xxx.com') as server:
    msg['To'] = receivers
    server.send_messages(msg)
    print(f"Successfully sent email to: {receivers}")