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URI in Windows 8 Metro Style App

Intr-o aplicatie Windows 8 Metro App putem sa specificam printr-un URI locatia de unde sa incarcam continutul unui fisier. Folosirea path-urilor absolute nu este recomandata, deoarece in mod normal nu avem acces la orite path. De exemplu daca folosim un path de forma: "C:\Foo\content.txt" o sa ne trezim cu o eroare de genul "Access is denied".
Este foarte important de stiut ca o aplicatie de tip Metro App are access doar la un numar limitat de locatii. Nu o sa avem access la orice locatie de pe masina. Singura varianta pentru a accesa locatii la care nu avem acces este ca userul sa specifice locatie prin intermediul unui file picker.
URI are urmatoare forma: [scheme]://[numeDomeniu]/[path]
[scheme] poate sa aibe 3 valori predefinite:
  • ms-appx - care va indica locatia unde este pachetul aplicatiei (locatia de unde ruleaza aplicatia)
  • ms-appdata - care indica locatia unde se salveaza datele pe care le-am downloadat de pe internet
  • ms-resource - locatia care contine fisiere de resurse localizabile
Numele de domeniu poate sa fie ignorat, caz in care se va folosii domeniul curent.
In exemplul de mai jos incarcam logo-ul aplicatiei din directorul 'images'.
IAsyncOperation<StorageFile> storageFileAsyncOp = StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///images/AppLogo.png""));

Enjoy!

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