door darting?

If you discipline, he'll feel that he is being scolded for coming back to you, which is what you WANTED him to do.  Rather, have him drag a lead and before you open the door for any reason, slip the hand hold over the knob.  Even if he tries to run, he won't get further than the length of the lead.  Safer and he should learn that way.

Glad that I could help! 

Julie has an excellent point with the emergency recall word.  Funny, I use bye with Tyler too.  Normally, "bye, see ya", when he gets stubborn on me off lead.  He sees my attitude as basically "she doesn't care....omg she might LEAVE me"

You were in a tough situation.  What sometimes works is to do something totally outrageous....like roll on the ground or make a noise like you've gotten hurt.

 Start walking away from the dog or  with your back turned kneel down and pretend that you have something very interesting.

 The other thing you might do, if your dog is crate trained and you have a crate available, is teach him that when he hears the doorbell ring, he should run to his crate, or alternatively you can provide him a mat or bed he should be on when you open the door.

http://www.youtube.com/watch?v=tVGaslyGaGE

A bit more difficult thing to do, but I have done it successfully in the past, not with a door darter, but one who would just charge the crap out of people, was teach the dog to read (there is a book, I believe called "Teach Your Dog to Read", which details this). I actually did manage to teach a dog to read, then posted a "sit" sign near the door, or wherever I just wanted the dog to sit if he got there.This is a more complicated option, and my recommendation would be that which others suggested, leashing him when you open the door, or teaching him to go to a specific place when you open the door. I would suggest though that if you are going to teach going to a place, you would need to manage with a leash until he learns what to do. 

You should also teach an emergency recall as suggested. This is a video which teaches you how to teach your dog a whistle recall. 

http://www.youtube.com/watch?v=ulVD2iYZsYI

Oh... and if your dog is used to walking on leash, showing him his leash might just work to get him back. I have no yard, so must walk my dogs on leash. For dogs who are used to walking on leashes, if they have a regular leash that you use, it's a pretty strong reinforcer, so they might just come back to you for a walk. This can also work with opening your car door if your dog enjoys going in the car. You have to be able to get the dog's attention in order for either of these to work, but often times you can do this just by shaking the leash. If you do walk your dog on leash, you might want to start making sure to shake the clip when you call your dog to come for a walk. This will start conditioning the sound of the leash clip shaking as a reinforcer, signaling that by coming, a walk is available. If your dog really enjoys walks, he might not realize he's giving up freedom. Food dishes can also be used in the same way. I use a metal food dish for my dogs. It can be very noisy when you fill it (which I always shake it around a bit). Again, a dog who has learned that a noisy metal bowl means food is coming, might just come running when he hears the metal dish.