高效的Esmtp,带验证，用Socket编写

return false;

string[] sendBuffer;

string enter = "\r\n";

sendBuffer = new String[9];

sendBuffer[0] = "EHLO " + smtpServerName + enter;

sendBuffer[1] = "AUTH LOGIN" + enter;

sendBuffer[2] = Base64Encode(userName) + enter;

sendBuffer[3] = Base64Encode(password) + enter;

sendBuffer[4] = "MAIL FROM:<" + from + ">" + enter;

sendBuffer[5] = "RCPT TO:<" + to +">" + enter;

sendBuffer[6] = "DATA" + enter;

sendBuffer[7] = "From:" + fromName + "<" + from +">" + enter;

sendBuffer[7] += "To:=?" + charset.ToUpper() + "?B?"

+ Base64Encode(recipientName) + "?=" + "<" + to + ">" + enter;

sendBuffer[7] += "Subject:" + "=?" + charset.ToUpper() + "?B?"

+ Base64Encode(subject) + "?=" + enter;

sendBuffer[7] += "X-Priority:" + priority + enter;

sendBuffer[7] += "X-MSMail-Priority:" + priority + enter;