"Hoş geldin ve güle güle!"
Translation:Welcome and goodbye!
For example, when some one leaves, He told me he was thankful for being invited to my party, & because the party is now over, so I would have to answer "You were welcome".
When someone is leaving a meeting and saying he was thankful for being invited, what would you answer in Turkish?
I don't think we have a sentence that covers all that meaning. But If you want to say "you're welcome" as a response to "thank you for invited me tonight" you can say "rica ederim." or "ne demek."
In Turkish: Tüm bu anlamı kapsayan bir cümle olduğunu sanmıyorum, ama eğer demek istediğin "bu gece beni davet ettiğin için teşekkür ederim" için bir cevapsa; "rica ederim." veya "ne demek" diyebilirsin.
I don't know why people are marking down a perfectly sensible comment by @amylbeam. We've only just start learning the language - that's a bit too soon to be making apparently contradictory jokes with words we still don't really know and expecting people to understand them.