communicate between Metatrader 4 and C#

Need a C# app that can send a trade to Metatrader 4 terminal. Also need to send a trade from Metatrader 4 to the C# app (just send the trade information, like size, pair, slippage, etc. Communication should be done with string, so that it is easy to modify later on. This project might require developing a mt4 script, dll, and simple C#, as I have created such projects before and that is the approach I used. You are free to use another method if it achieves the same purpose.