Develop a simple Windows Forms Application of your own choice. (language C#)

It should take user input from one or several text boxes, perform some data manipulation, and display the result.

Your application should use at least 5 of the following features (if you like, use more than 5, and add any additional features):

1. Variables
2. Button(s), Textbox(es)
3. Label(s),
4. MessageBox
5. IF statement
6. Loop
7. Listbox
8. Array or List
9. Method(s)
10. String Processing (SubString, concatenation)

Document your application and include into .DOC file:

• explanation of the purpose of the application
• source code with comments (recommended length: 50-100 lines of code, including comments)
• screenshots of the application run-time, demonstrating at least 3 different results, based on input provided.