Windows Store WinJS app - how to pass query string, hash parameters to start page - windows-store-apps

Question

We have a SPA web application that we're trying to convert into a WinJS project as a native Windows Store app. For most part, the Javascript is working except for DOM manipulations deemed unsafe.
One thing that does not appear apparent is, how can the start page of the app (e.g. index.html) be supplied with query string and hash parameters? Our site main page is designed to behave differently based on parameters.
e.g. index.html?contextId=xxxxx#enviroment=xxxxx
I tried adjusting the value in package.appxmanifest to no avail. It will throw errors on query strings, and hash parameters will silently not persist.
UPDATE: Project background
A brief about what our app does, and then why the above naive desire won't work and the answer below how we went about this issue.
Our web app is a highly-dynamic data-driven application that completely relies on data to figure out what to render. Therefore the ?contextId=xxxxx parameter is so crucial as it tells our system to load the data which further informs what kinds of visual components to load and it goes on recursively to form wildly different UIs.
We were looking to therefore find some means to supply these parameters like traditional command-line parameters to the same executable to produce different UIs. And thus different "apps" by mere changes in those parameters. Like a "config transform" mechanism for web.config in ASP.NET web projects, that would be most welcome.
However further testing showed it is not possible; a single Windows store app project has a GUID that is supplied into the packaged app bundle. Building the same project multiple times with different "build config" would just mean overwriting a previous installation since they are the same app with increasing version numbers. The answer details how we went about this.

Answer 1

Windows Store apps don't work with URI parameters when launched from their primary tile. In that case, you should make sure that the app defaults to suitable values, e.g., if you were thinking to supply defaults in the manifest, then default to those in the app's activation handler for the ActivationKind.launch case when eventObject.detail.arguments is empty.
There are two other ways to launch an app that can supply other arguments.
First is to launch via a secondary tile. When you create the tile from the app (which is subject to user consent), you supply the launch arguments. In your activation handler, for ActivationKind.launch, those args will be in the eventObject.detail.arguments property.
Second is to launch the app through a URI association. You use a custom schema for this, which is declared in the manifest. The app will then see ActivationKind.protocol and eventObject.detail.uri will contain the full URI including any parameters. A URI launch can be done from another app, by entering the URI into a browser address bar, or through a shortcut that a user could configure on the Start screen.

Answer 2

The first step is to convert our Windows (8.1) Store project into a Universal app structure, which would then spin off a separate Windows Phone WinJS project (this is nice when we wish to target Windows Phone later) and a shared project.
Practically everything from the Windows Store project is moved to the shared project (including default.html or index.html). What remains in the Windows Store project is a customised config.js carrying the parameters
window.customWin8 = {
contextId: xxxxxxxxxx,
customParam: 'xxxxxxxxxx'
};
The downstream modules that sense for query string/hash parameters would then fall back to this alternative object if it exists to pick up the data it needs.
Now, for every differing app we wish to deploy, that would for now seem to require a separate Windows Store project so it gets its own GUID and won't conflict with other apps. All these projects would reference the very same shared project thanks to the Universal structure Visual Studio affords. The only down side is it seems Visual Studio 2013 does not have a direct UI method to make this referencing to the share project and has to be hand code into the jsproj file.
<Import Project="..\Common.Shared\Common.Shared.projitems" Label="Shared" />
With this adjustment they can all build and package with their isolated "build config".