如何检查电子邮件地址是否正确和存在？
问题描述：
可能重复：
如何检查电子邮件地址是否存在，而不发送电子邮件？
我想知道：有没有办法检查电子邮件地址是否正确 在发送电子邮件之前，使用 Telnet 或 SMTP协议cmd-line ？
I was wondering : is there a way to check if an email address is Correct and it Exists before sending an email, using Telnet or SMTP Protocol cmd-line ?
答
检测电子邮件地址是否存在的唯一有效解决方案是发送电子邮件并等待回答。
The only valid solution to detect if an email address exists is to send an email and wait for answer.
大多数时候，您也想确保您的用户是帐户的所有者，此解决方案同时进行两项检查。
Most of the times you also want to be sure that your user is the owner of the account, and this solution does both checks.
您不能仅在客户端进行操作，您需要一个服务器端API。
You can't do this client-side only, you'll need a server-side API.