Programming Homework Help

I need help with a C# question. All explanations and answers will be used to help me learn.

Develop a simple Windows Forms Application of your own choice, it should be about any topic of your interest:

• 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           
  11. 1-  explain the purpose of this application
  12. 2- demonstrate run-time in various scenarios
  13. 3- explain how it works, browsing through your source code.