Part 4 of this project

Data Layer

Model a workbook as rows and columns in memory

Goal for this part

Model a workbook as rows and columns in memory.

Treat 04-Data-Layer as the source of truth for this checkpoint. If your local tree drifted, re-clone that folder rather than mixing files from neighbors.

What you should already know

You do not need prior WPF experience for part 1. Later parts assume you finished the earlier snapshots on the same machine.

  • .NET 8 SDK is installed
  • You can run dotnet from a terminal
  • WPF snapshots target Windows

Why WPF fits Gridlane

WPF’s DataGrid is a natural teaching surface for cells, formulas-lite, and clipboard paste—without building a full Excel clone.

Bind a 2D cell model to the grid. Keep parsing and file I/O out of code-behind event handlers as the sheet grows.

Checkpoint

After you run the snapshot, you should recognize the behavior described in the goal—before you move on. If the window (or server) never appears, stop and fix the run steps.

Code shape

Snapshots stay small on purpose. Look for this kind of core call as you read the folder:

File.WriteAllLines(path, rows.Select(r => string.Join(",", r)));

How to run it

Clone the teaching repo, open 04-Data-Layer, install what the README asks for, then run dotnet run.

git clone https://github.com/michaeldunga1/fcc-wpf-spreadsheet.git
cd fcc-wpf-spreadsheet/04-Data-Layer
dotnet restore
dotnet build
dotnet run

Common mistakes

  • Ignoring platform-specific install notes in the snapshot README
  • Creating tables twice with conflicting schemas
  • Forgetting to commit/close the database connection in long sessions
  • Looking for seed data in part 3 before the data layer exists