Building a WinForms PDM From Scratch

Special-build belt drawings once hid behind cryptic numbers. By introducing attribute-level parsing, a lightning-fast filter panel, and clean Dependency Injection (DI), our WinForms PDM now surfaces matches in ~2 seconds instead of 5 plus — a 50 % improvement that lets engineers reuse instead of redraw.

SDLC Highlights in Three Sprints

1 · Requirements & Analysis

Problem: Search limited to filename; junior drafters spent ~5 minutes hunting.

Solution: Break drawing number into 14 attributes (series, width, color, etc.) then expose each as a filterable column.

Impact: Lookup time dropped by half; tribal memory no longer required.

• Stakeholder workshops gathered 12 must-have attributes and 8 nice-to-haves.
• Used MoSCoW prioritisation to shape the sprint backlog.

2 · Architecture & Design Patterns

Dependency Injection (DIP) —Program.cs boots ServiceCollection then resolves Form1; forms no longer create their own services.

Repository / Service pattern —DrawingFileService abstracts JSON vs network lookup.

Strategy —IDrawingNumberDecipherService is pluggable for future product lines.

SOLID guidance ensures each class has one reason to change.

3 · Sprint-by-Sprint Evolution

Problem: Static filter mock-up, no DI.

Solution: Hooked DataGrid double-buffering & basic search.

Impact: First demo proved concept to leadership.

Problem: Filters slow with 10 000+ rows.

Solution: Parallel LINQ (PLINQ) on file scan; binding lists.

Impact: Load time dropped from 18 s → 6 s.

Problem: Context menu & attribute panel missing.

Solution: Added right-click actions, logger, live decipher grid.

Impact: Users complete full lookup + open drawing in under 30 s.

4 · Testing & Hardening

xUnit tests validate 40 + drawing-number permutations.

Smoke-test script ensures DI container builds on startup.

5 · Deployment & Maintenance

ClickOnce installer to internal file-share; config JSON points to K:\ drive.

Serilog sinks to rolling JSON for analytics.

Future: migrate UI to Blazor Hybrid while reusing all services.

// Program.cs — DI bootstrap
var services = new ServiceCollection();
services.AddScoped<IDrawingFileService, DrawingFileService>();
services.AddScoped<IDrawingNumberDecipherService, DrawingNumberDecipherService>();
services.AddHttpClient();
services.AddScoped<Form1>();
using var provider = services.BuildServiceProvider();
Application.Run(provider.GetRequiredService<Form1>());

// DrawingNumberDecipherService.cs — Strategy + SRP
foreach (var (attr, max, lookup) in metadata)
{
    string code = drawingNumber.Substring(idx, max);
    idx += max;
    string value = lookup(code); // maps code → human attr
    result[attr] = (code, value);
    _logger.LogInformation("{Attr}:{Code}->{Val}", attr, code, value);
}

Three sprints, clean architecture, and relentless user feedback turned a shared drive into an insight-driven PDM. Sprint-4 will layer AI suggestions and Blazor-Hybrid UI — stay tuned!