如何发送带有日历请求的电子邮件（内容类型：文本/日历）

Question

我尝试将icalendar代码嵌入到通过indy发送的内容类型为文本/日历的电子邮件中，但当我添加为附件时，它只是挂在电子邮件的编码上，它只是作为附件到达，并且不会提示其他日历请求即可。有没有人有如何通过 indy 执行日历请求的示例代码？

Answer 1

这是 RRUZ 示例的替代方案：

program SendMailWithCalendarRequest; 
{$APPTYPE CONSOLE} 

uses 
  IdSMTP, 
  Classes, 
  DateUtils, 
  IdMessage, 
  SysUtils; 

 procedure SendCalendarRequest; 
 var 
  SMTP        : TIdSMTP; 
  MailMessage : TIdMessage; 
 begin 
   SMTP:= TIdSMTP.Create(nil); 
   MailMessage := TIdMessage.Create(nil); 
   try 
     SMTP.Host := 'smtp.mailserver.com'; 
     SMTP.Port := 25; 
     SMTP.Username := 'the account'; 
     SMTP.Password := 'the password'; 
     SMTP.AuthType := satDefault; 
     MailMessage.From.Address := '[email protected]'; 
     MailMessage.Recipients.EMailAddresses := 'the Recipient'; 
     MailMessage.Subject := 'Send calendar'; 
     MailMessage.Body.Add('BEGIN:VCALENDAR'); 
     MailMessage.Body.Add('VERSION:1.0'); 
     MailMessage.Body.Add('BEGIN:VEVENT'); 
     MailMessage.Body.Add('ORGANIZER:MAILTO:'+SenderMail); 
     MailMessage.Body.Add('DTStart:'+FormatDateTime('YYYY-DD-DD',Now)); 
     MailMessage.Body.Add('DTEnd:'+FormatDateTime('YYYY-DD-DD',  Tomorrow)); 
     MailMessage.Body.Add('Location;ENCODING=QUOTED-PRINTABLE: My home'); 
     MailMessage.Body.Add('UID:'+FormatDateTime('YYYY-DD-DD',Now)+FormatDateTime('YYYY-DD-DD', Tomorrow)); 
     MailMessage.Body.Add('SUMMARY:Appointment Reminder'); 
     MailMessage.Body.Add('DESCRIPTION:Test message'); 
     MailMessage.Body.Add('PRIORITY:5'); 
     MailMessage.Body.Add('END:VEVENT'); 
     MailMessage.Body.Add('END:VCALENDAR'); 
     MailMessage.ContentType := 'text/calendar';
     SMTP.Connect; 
     try 
       try 
         SMTP.Send(MailMessage) ; 
         Writeln('OK') 
       except on E:Exception do 
         Writeln(0, 'ERROR: ' + E.Message) ; 
       end; 
     finally 
       SMTP.Disconnect; 
     end; 
   finally 
    SMTP.Free; 
    MailMessage.Free; 
   end; 
 end; 

begin 
  try 
    SendCalendarRequest; 
    readln; 
  except 
    on E: Exception do 
      Writeln(E.ClassName, ': ', E.Message); 
  end; 
end. 

Answer 2

@David，如果您将属性设置为 ContentType:='text/calendar'，电子邮件客户端会将附件识别为日历请求，请参阅此链接以获取 iCalendar 格式规范

请参阅此示例代码（在 Delphi 2010 中测试）

program SendMailWithCalendarRequest;
{$APPTYPE CONSOLE}


uses
  IdSMTP,
  Classes,
  DateUtils,
  IdAttachmentFile,
  IdMessage,
  SysUtils;

 procedure SendCalendarRequest;
 var
  SMTP        : TIdSMTP;
  MailMessage : TIdMessage;
  Calendar    : TStrings;
  CalendarFile: String;
  Attachment  : TIdAttachmentFile;
  SenderMail  : String;
 begin
    SenderMail:='[email protected]';
    CalendarFile:=ExtractFilePath(ParamStr(0))+'\appmnt.vcs';
    Calendar:=TStringList.Create;
    try
        Calendar.Add('BEGIN:VCALENDAR');
        Calendar.Add('VERSION:1.0');
        Calendar.Add('BEGIN:VEVENT');
        Calendar.Add('ORGANIZER:MAILTO:'+SenderMail);
        Calendar.Add('DTStart:'+FormatDateTime('YYYY-DD-DD',Now));
        Calendar.Add('DTEnd:'+FormatDateTime('YYYY-DD-DD',  Tomorrow));
        Calendar.Add('Location;ENCODING=QUOTED-PRINTABLE: My home');
        Calendar.Add('UID:'+FormatDateTime('YYYY-DD-DD',Now)+FormatDateTime('YYYY-DD-DD',Tomorrow));
        Calendar.Add('SUMMARY:Appointment Reminder');
        Calendar.Add('DESCRIPTION:Test message');
        Calendar.Add('PRIORITY:5');
        Calendar.Add('END:VEVENT');
        Calendar.Add('END:VCALENDAR');
        Calendar.SaveToFile(CalendarFile);
    finally
    Calendar.Free;
    end;

   SMTP:= TIdSMTP.Create(nil);
   MailMessage := TIdMessage.Create(nil);
   try
     SMTP.Host := 'smtp.mailserver.com';
     SMTP.Port := 25;
     SMTP.Username:='the account';
     SMTP.Password:='the password';
     SMTP.AuthType:=satDefault;
     MailMessage.From.Address := SenderMail;
     MailMessage.Recipients.EMailAddresses := 'the Recipient';
     MailMessage.Subject   := 'Send calendar';
     MailMessage.Body.Text := '';
     Attachment:=TIdAttachmentFile.Create(MailMessage.MessageParts, CalendarFile) ;
     Attachment.ContentType:='text/calendar';//set the content type to text/calendar
     try
       try
         SMTP.Connect;
         SMTP.Send(MailMessage) ;
         Writeln('OK')
       except on E:Exception do
         Writeln(0, 'ERROR: ' + E.Message) ;
       end;
     finally
       if SMTP.Connected then SMTP.Disconnect;
     end;
   finally
    SMTP.Free;
    MailMessage.Free;
   end;

 end;

begin
  try
    SendCalendarRequest;
    readln;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
end.