C# 3.0 Design Patterns

Exercises

1. Implement the final stage of the Photo Group application, which involves fetching and displaying an image (extrinsic state) when its thumbnail (intrinsic state) is clicked.

2. Integrate the Photo Library and Photo Group applications so that commands can be issued as well as photos displayed. Keep track of the two patterns (Composite and Flyweight) and report at the end of the exercise how they fit together.

3. In the earlier Composite pattern example (Example 3-3), the specification of the Photo Library was read from a file. As an exercise in object initialization, specify the initial state of the library in the program using the same data:

   AddSet Home
   AddPhoto Dinner.jpg
   AddSet Pets     Going down another level
   AddPhoto Dog.jpg
   AddPhoto Cat.jpg
   Find Album      Ensures Garden is at same level as Home
   AddSet Garden
   AddPhoto Spring.jpg
   AddPhoto Summer.jpg
   AddPhoto Flowers.jpg
   AddPhoto Trees.jpg

   (Hint: take these lines out of the data file. The program won't have to change otherwise, as the loop will start processing from the first command it finds in the file, which will be Display.)