Zoo 1.4 Walkthrough

You will update the project to use constructor-based setup and validation so objects begin with useful values when they are created.

Exact casing matters

File names, UI names, display text, event handler names, method names, field names, and property names may be case-sensitive. Match the provided starter and completed checkpoint naming exactly.

Common mistake to check

Most issues in this kind of checkpoint come from one character being different: a missing capital letter, a renamed event handler that does not match XAML, or a class file that was created outside the expected folder.

How to use the code snippets

Code snippets show only the lines to add or change. Do not recopy surrounding code that is already in the file. Place each snippet inside the correct class, method, property, or XAML area so the braces and tags still make sense.

Before You Start

Back up your completed Zoo 1.3 LastName folder first. Then copy or rename your working folder and solution file so they use Zoo 1.4 LastName. Use your actual last name in place of LastName.

Make a backup copy of your completed previous checkpoint before editing.

Open the copied working folder in Visual Studio, not the archived backup.

Confirm the project opens and builds before you make this checkpoint's changes.

Check Your Work

You will update the project to use constructor-based setup and validation so objects begin with useful values when they are created. After you finish the edits, verify the project instead of only checking that the code looks similar.

Temporary screenshot location: Check Your Work.

Build, run, and inspect the checkpoint behavior.

Build the solution. A successful build means the compiler can find the classes, members, namespaces, and event handlers.
If the build fails, read the first error message carefully before changing several things at once.
If a class, method, field, property, or event handler is not recognized, compare exact casing with the walkthrough and the target code.
Run the project and click the buttons that were added or changed in this checkpoint.
Use a breakpoint in the edited event handler or business-class method if a button runs but the result is not what you expected.

1.4 Zoo Learning Activity

Before You Start

Check Your Work