Forward Mails Based on Search Criteria

Have you ever wanted to forward all mails that matching a search expression? That option is not available through the Gmail interface but it is relatively easy to do that with a script.

An example of the script is as follow:

function forwardMail() {
  var threads = GmailApp.search("before:2009/07/01 after:2009/06/30"); // second search string.
 
  for (var i in threads) {
    var lastMsg = threads[i].getMessageCount(); //get last message
    var messages = threads[i].getMessages();
   
    var message = messages[0]; //first mail in the thread
    //var message = messages[lastMsg-1]; // last mail in the thread
    message.forward("strovek@seagate.com");
   
  }
}

Notes:

In the example above, you can use messages[0] to select the first message in a thread or messages[lastMsg-1] for the last message in a thread.  The last message will usually contains most of the replies of the threads if the participants are the same throughout the thread conversations.



To make sure you get the mails you want to forward, test the search expression in Gmail first.