Python调用系统默认邮件客户端并自动添加附件的方法问询

1. Windows系统通用邮件客户端调用（无需Outlook） #

通过Python的ctypes调用Windows shell32 API，可调用系统默认邮件客户端并添加附件，支持Thunderbird、Windows Mail等主流客户端：

import ctypes
from ctypes import wintypes

class SHELLEXECUTEINFO(ctypes.Structure):
    _fields_ = [
        ("cbSize", wintypes.DWORD),
        ("fMask", wintypes.ULONG),
        ("hwnd", wintypes.HWND),
        ("lpVerb", wintypes.LPCSTR),
        ("lpFile", wintypes.LPCSTR),
        ("lpParameters", wintypes.LPCSTR),
        ("lpDirectory", wintypes.LPCSTR),
        ("nShow", wintypes.INT),
        ("hInstApp", wintypes.HINSTANCE),
        ("lpIDList", wintypes.LPVOID),
        ("lpClass", wintypes.LPCSTR),
        ("hkeyClass", wintypes.HKEY),
        ("dwHotKey", wintypes.DWORD),
        ("hIconOrMonitor", wintypes.HANDLE),
        ("hProcess", wintypes.HANDLE)
    ]

SEE_MASK_NOCLOSEPROCESS = 0x00000040
SEE_MASK_INVOKEIDLIST = 0x0000000C

def send_mail_with_attachment(to, subject, body, attachment_path):
    shell32 = ctypes.WinDLL("shell32.dll")
    sei = SHELLEXECUTEINFO()
    sei.cbSize = ctypes.sizeof(SHELLEXECUTEINFO)
    sei.fMask = SEE_MASK_NOCLOSEPROCESS | SEE_MASK_INVOKEIDLIST
    sei.lpVerb = b"open"
    # 处理含空格的附件路径
    attachment = f'"{attachment_path}"' if " " in attachment_path else attachment_path
    sei.lpFile = b"mailto:" + to.encode('utf-8')
    sei.lpParameters = f"?subject={subject}&body={body}&attachment={attachment}".encode('utf-8')
    sei.nShow = 1  # SW_SHOWNORMAL
    if not shell32.ShellExecuteExA(ctypes.byref(sei)):
        raise ctypes.WinError()

# 使用示例
send_mail_with_attachment(
    to="recipient@example.com",
    subject="测试邮件",
    body="这是测试邮件内容",
    attachment_path=r"C:\test\file.txt"
)

2. 跨平台：调用邮件客户端CLI命令 #

针对不同客户端的命令行接口直接调用，先检测系统已安装客户端再选择对应方式：

• Thunderbird：

  import subprocess
  import shlex
  
  def send_with_thunderbird(to, subject, body, attachment_path):
      cmd = f'thunderbird -compose "to={to},subject={subject},body={body},attachment={attachment_path}"'
      subprocess.run(shlex.split(cmd), check=True)
  

• Apple Mail（macOS）：

  import subprocess
  import shlex
  
  def send_with_apple_mail(to, subject, body, attachment_path):
      cmd = f'open -a Mail "mailto:{to}?subject={subject}&body={body}&attachment={attachment_path}"'
      subprocess.run(shlex.split(cmd), check=True)
  

3. 浏览器引导网页邮件服务（如Gmail） #

构造网页邮件的撰写URL，用浏览器打开，用户手动添加附件并输入密码：

import webbrowser
import urllib.parse

def open_gmail_compose(to, subject, body):
    params = {
        'to': to,
        'subject': subject,
        'body': body
    }
    encoded_params = urllib.parse.urlencode(params)
    gmail_url = f"https://mail.google.com/mail/u/0/#compose?{encoded_params}"
    webbrowser.open(gmail_url)

# 使用示例
open_gmail_compose(
    to="recipient@example.com",
    subject="测试网页邮件",
    body="这是通过Gmail网页版发送的测试内容"
)

4. 第三方库辅助：plyer #

跨平台库plyer提供统一接口调用系统默认邮件客户端，支持多平台：

from plyer import email

def send_mail_plyer(to, subject, body, attachment_path):
    email.send(
        recipient=to,
        subject=subject,
        text=body,
        attachments=[attachment_path]
    )

内容的提问来源于stack exchange，提问作者JadeCeci