VC++STMP发信

procedure TSMTPForm.btnSendClick(Sender: TObject);

begin
MemoInfo.Clear;
//1:对所必须要的信息进行进行检验

//校验服务器属性
if (Trim(HostName.Text)='') or (Trim(HostPort.Text)='') then
begin
ShowMessage('请设置所要连接的SMTP服务器属性！');
HostPort.Text:='25';
HostName.SetFocus;
Exit;
end;
//检测地址信息
if (Trim(EditFrom.Text)='') or (Trim(EditTo.Text)='') then
begin
ShowMessage('请输入收信人或者发信人地址！');
EditFrom.SetFocus ;
Exit;
end;
//用户账号检验
if (Trim(EditUser.Text)='') or (Trim(EditPass.Text)='') then
begin
ShowMessage('请正确输入用户登录帐号和密码！');
EditUser.SetFocus;
Exit;
end;
//对MailMessage属性进行赋值
with MailMessage do
begin
Subject := EditSubject.Text; //邮件主题
Body.Assign(MemoMesg.Lines);//邮件正文
From.Address:=Trim(EditFrom.Text); //发信人地址
Recipients.EMailAddress