Sessions, Statics, and Multi-User Safety

From WinForms to the WebModule 4The lesson guide, the walkthrough video, the knowledge check and the hands-on lab this sample was built from are on learnwisej.com — free, with an AI tutor in every lesson.

Open the course

Every static field and singleton of LegacyOrderDesk is found and classified (keep static vs move to session / profile store / browser storage), the five per-user statics of AppState become a typed UserSessionContext behind Application.Session, and the Orders screen is tested with two browser sessions: changing the filter in one does not affect the other. Sign out runs the one cleanup routine the lesson asks for.

The source of this sample

iceteagroup/LearnWisej-SamplesFrom WinForms to the Web Course/Module 4

Browse this folder on GitHub

Or clone it: git clone https://github.com/iceteagroup/LearnWisej-Samples.git — then open OrderDesk.Web.slnx in Visual Studio and press F5.

Run it

cd "LearnWisej-Samples/From WinForms to the Web Course/Module 4/OrderDesk.Web"
dotnet run -f net10.0 --urls http://localhost:5604

Then open http://localhost:5604. (Visual Studio: open OrderDesk.slnx, F5.)

What to try

Action	What you should see
Page load	The Orders card with all 5 orders and the Session card: User (not signed in), Active filter All
Sign in as kelly	The context becomes kelly · Acme · Northwind Traders · filter Open: the combos follow, the grid shows 2 of 5 orders (Northwind highlighted), the Session card shows the four values
Sign in as sam	sam · Globex · Fabrikam Inc · filter Invoiced: 1 of 5 orders
Filter / customer combos	Write to this session's context and re-filter the grid
Open second session ↗ → in the new tab Sign in as sam and change its filter → back in the first tab Re-read state	The first tab still shows kelly's customer and filter: each session reads its own UserContext (steps in docs/TwoSessionTest.md)
Sign out	SessionCleanup.Run deletes the session's temp folder and SessionContext.Reset() clears only this session's context; the other tab is untouched

Where things live

Module 4/
└─ OrderDesk.Web/                     the Wisej.NET 4 app (net10.0-windows;net10.0), port 5604
   ├─ Program.cs / Startup.cs         session entry point (Application.MainPage + the ApplicationExit cleanup) / Kestrel host
   ├─ Default.html / Default.json / Web.config
   ├─ Domain/                         the reused business logic (Order, Customer, OrderService, CustomerService, InvoiceDocument, SampleData)
   ├─ Services/UserSessionContext.cs  the typed context: plain data, no Wisej reference
   ├─ Services/SessionContext.cs      Current (lazy, per browser session in Application.Session) + Reset()
   ├─ Services/SessionCleanup.cs      the one routine logout and ApplicationExit share
   ├─ Services/StorageRoot.cs         Web.config OrderDesk.StorageRoot (default App_Data)
   ├─ Views/Ui.cs                     colours + toast helper
   ├─ MainPage.cs / .Designer.cs      the Orders screen + the Session card
   ├─ App_Data/                       created at run time: tmp/<session>/report-job.txt
   └─ docs/                           the lab deliverables + migration-log.md

Runtime facts

• Application.Session is a dynamic bag (also a Dictionary<string, object>): a member that was never set reads as null. SessionContext.Current wraps exactly that and creates the context lazily.
• Application.ApplicationExit is a static event: subscribed once per session in Program.Main, it runs even after the page is disposed. It has no UI to push to — log to the host, do not touch controls.
• Application.Navigate(Application.Url, "_blank") opens a second session in the same server process; Application.SessionCount counts them; Application.SessionId identifies this one.
• Application.StartupPath is the project folder under dotnet run, so App_Data/tmp is created next to the sources; delete App_Data/ to reset the sample.
• The projects multi-target net10.0-windows;net10.0, so dotnet run needs -f net10.0 (or -f net10.0-windows).