go - 向多个收件人发送 smtp 电子邮件

Question

我正在使用 this发送 smtp。它适用于一个接收器，但我想要多个接收器。我尝试了以下方法:

func sendemail(body string) {  
    from := "smtpemail" 
    pass := "pass"
    to := "a@gmail.com,b@gmail.com"
    ....
}

我也试过:

to := "\"a@gmail.com\",\"b@gmail.com\""

和:

to := []string{"a@gmail.com","b@gmail.com"}

它们都不起作用。抱歉，太简单了，我刚开始使用 golang。

Answer 1

来自 net/smtp 文档:

The msg parameter should be an RFC 822-style email with headers first, a blank line, and then the message body. The lines of msg should be CRLF terminated. The msg headers should usually include fields such as "From", "To", "Subject", and "Cc".

RFC 822要求 To: header 值是逗号分隔的列表。因此，虽然 to 变量应该保持为 []string 并作为其 to 参数传递给 smtp.SendMail , 邮件标题(在消息中)应该以逗号分隔的列表形式出现。试试下面看看它是否有效:

func send(body string) {
    // ...
    to := []string{"foo@mailinator.com", "bar@mailinator.com"}
    toHeader := strings.Join(to, ",")

    msg := "From: " + from + "\n" +
        "To: " + toHeader + "\n" + // use toHeader
        "Subject: Hello there\n\n" +
        body

    err := smtp.SendMail("smtp.gmail.com:587",
        smtp.PlainAuth("", from, pass, "smtp.gmail.com"),
        from, to, []byte(msg))

    // ...
}