Open with in csharp

Question

How to put your Windows application form in C # in the open with Windows list
Note: If you right-click on a file, such as a txt file in Windows, and select open with, you can open the file with a special program.
I will be grateful

Answer 1

No Martin I want to create a new program that can open with
For example I created a program that can open txt files I want to make that file can be open with [just in your answer]
No open with other files like notepad
Ok?