Delegates is mainly used with events.
The need is:
You do not want to execute a piece of code at the time when you run the program.
After running the program you want to execute that piece of code whenever an event occurs.
Example :
- Console application - code can be executed only at the time you run the program. (Written inside Main method)
- Windows application (user interface programming ) - code can be executed when clicking the button after running the program.
This is what they say, you do not know which method will invoke at compiling time. you know it only at runtime that is when clicking the button.
Without delegates no user interface programming is possible. Because you are executing code whenever the user makes events that is clicking button , typing in textbox, selecting dropdownlist item and so on....
