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What's the default file path in WinRT/WP 8.1?

Hello fellow programmers.
I recently made a mistake while using the SQLite-NET package for Windows Phone 8.1. When opening a new SQLiteConnection, I would give as parameter to its constructor the string "data.db", without being actually aware of what was going on under the hood. Later on, I noticed that the file wouldn't be deleted, even if I uninstalled the application (since I would have in my app the same entries that I had before uninstalling it); I assume that I should be using the local folder for application data instead.
However, here is the real question: what the hell is the folder where the data.db file was created? I tried to figure it out with the following piece of code:
var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///data.db"));
System.Diagnostics.Debug.WriteLine(file.Path);
and what I got as output of the WriteLine method was the path
C:\Data\SharedData\PhoneTools\AppxLayouts\f7529f24-ba24-4fdb-8353-cff9214180a0VS.Debug_ARM.Valbrand\data.db,
which only got me even more confused. I couldn't find any satisfactory info on this, and I would REALLY like to further my understanding of what happened here.
Thanks in advance!

The path you are looking at is the install directory of your app. You have a Silverlight 8.1 app, so the path is slightly different than a Silverlight 8.0 app, but the articles here and here will help you get a rough understanding.
The recommended usage of this directory is to take the resources that you want backed up out of it on first run and move them to the app data container, so they can be backed up by the system.

C:\Data\SharedData\PhoneTools\AppxLayouts\f7529f24-ba24-4fdb-8353-cff9214180a0VS.Debug_ARM.Valbrand\data.db
This is the path on your phone/emulator.
And This is not the location where you can find in your PC.

Windows Form Application : Publish issue

I'm very new to Visual Studio 2010. I decided to create a simple WFA with C#.
Everything work fine with Images and Audio playback. My intention is to create a standalone application and send it to my friend as a gift. Problem I facing now is that when I tried to publish the application, the Images / Audio is still using the same location in my PC. So it won't play nor display any images.
Any comment on this or guide for me? I did try search for solution but doesn't seems to have any luck.
This is the code that I used to play Audio :
SoundPlayer ply = new SoundPlayer(#"C:\Users\Liam619\Documents\Visual Studio 2010\Projects\BirthdayApp\BirthdayApp\Resources\BirthdaySong.wav");
If I remove or change the path, the Application will hit error for locating the Audio file.

There may be several solutions to your problem.
a) embed the sound into a resource. As a beginner, resources may be a bit tricky to get it right the first time. But I want to encourage you reading something about it. You'll need resources when you want to translate your first program.
b) create an installer which copies the sound file to the installation directory. Try InnoSetup. If you're a programmer, sooner or later, you'll need to create a Setup anyway. Always worth knowing how to do that.
In that case, you still need the path to the sound file, but if you install your EXE into the same path as the sound file, see getting the application's executable directory.

everything in the database whether images or audio refers to your own server database.you have to send the database too with the app and the correct version .NET framework needs to be installed on the target PC.

Windows Phone 8 UnauthorizedAccessException when opening file

I am having a very strange error when trying to access a ".stl" file in the "Stl" folder of my application when the app is downloaded from the Windows Phone Marketplace. It does not exhibit this behavior when it is launched from Visual Studio 2012 Express in either debug or release mode. Once I try loading a file it gives me an "System.UnauthorizedAccessException Access to path 'C:\Data\Programs\APPUID\Install\Stl\test.stl' is denied" exception while accessing a ".gcode" file in an almost exactly the same fashion from the "GCode" causes no error what so ever.
I have no idea what could be causing this or how to debug this because I don't know if I can somehow attach the debugger to an instance of the store downloaded app.
I also have no idea what could possibly be different between deploying the exact same app from the store and from Visual Studio. The Visual Studio installed app also does not give any troubles if the app is launched from the phone without the debugger being attached.
Any ideas?
PS. The file is being opened by a filestream which is then used by a binarreader. I am not sure if the source code is really needed and for which part but the important line is just:
FileStream fileStream = new FileStream(filePath, FileMode.Open);
Where "filePath" in this case is "Stl\test.stl".

Without seeing your actual code it is hard to say what the problem is. So instead of attempting to read your mind I will offer an alternative solution.
I have worked extensively with Isolated Storage on the Windows Phone and I have learned this.
There is no library, no API, no SDK, no Web service, in the world, that has worse error reporting than the Isolated Storage on windows phone.
EVERYTHING is Invalid Access or Unauthorized Access with ZERO further information.
To remedy this I created a DLL that serializes objects to the Isolated Storage for you.
All you have to do is put [DataContractAttribute] above your class name and [DataMemeber] above any variable you want saved. Then you just pass your object and unique name into the savefile method. That's it! Instant save
You can find my free DLL EZ_Iso.dll for download here. With example code and instructions
The code is open source so if you wish you may also decompile the dll and see how it all works.
Feel free to reach out to me here or on twitter if you have any questions or enhancements.

Ok I figured it out. The "install" directory is actually restricted access but for some reason the Visual Studio signing process leaves the app with enough permissions to access this folder. The correct procedure of determining a relative directory is not to use "Directory.GetCurrentDirectory()" but rather to use "ApplicationData.Current.LocalFolder". Hope this helps!

windows phone 8, applicationsettings not persisted

I have the following strange behaviour in my Windows phone 8, C# App.
I am saving a Setting with:
private void SaveProperty<T>(T property, string propertyName)
{
if (IsolatedStorageSettings.ApplicationSettings.Contains(propertyName))
IsolatedStorageSettings.ApplicationSettings[propertyName] = property;
else
IsolatedStorageSettings.ApplicationSettings.Add(propertyName, property);
IsolatedStorageSettings.ApplicationSettings.Save();
}
When the app runs, I can read all settings I stored in IsolatedStorageSettings.ApplicationSettings.
But when I re-open my app (open it from the app list), the IsolatedStorageSettings.ApplicationSettings-Dictionary contains Zero (0) Keys and Values.
Am I missing something?
I used the ISETool.exe to take snapshots of the IsolatedStorage of my app (thanks to chepene).
I saw this behaviour: when I wrote the Settings (that means after the SaveProperty<T>() function finished), and the app is still running, I have the Settings saved in _ApplicationSettings. This agrees with my Observation that I can read from the IsolatedStorageSettings.ApplicationSettings when the app is running.
The _ApplicationSettings-file also exists when the is tombstoned or not running (when I can Access it by Holding the back-button of the phone and when the app is closed with the back-button).
But when the app is opened again (via the app list), the _ApplicationSettings-file is gone...
I also see that, when I'm writing a file into the IsolatedStorage with:
SharedStorageAccessManager.CopySharedFileAsync(
Windows.Storage.ApplicationData.Current.LocalFolder, fileName+"orig",
Windows.Storage.NameCollisionOption.ReplaceExisting, fileID);
and when I then don't read this file, it is gone when I open the app the next time.
By the way, to avoid confusion: I am not reinstalling the app each time I open it.
If you need more Information please ask.
Any help appreciated.

With AppSettings, I've seen something similar on WP7/7.5, but it happened only when my property-value's type was a class that was not known to the serializer.
Are you sure that there were no exceptions:
during Save
during App Exit (since the App may dump the settings at that point)
during the time that App loads the settings for the first time after launch?
Note that this doesn't necessarily must mean the app crashing. I mean, any exceptions, those internally silenced or user-handled too. Please check the VisualStudio's Output panel for "first chance exceptions" log. If any I/O or security or serialization exception shows up, then investigate there. If i remember well, there's even a whole set of isolated-storage exceptions that are easily interceptable from debug/exceptions menu.
However, the issues I had with unknown or nonserializable types does not explain at all why your extra non-appsettings files would evaporate.
Another thought: maybe some additional tool performs something like 'clean deploy' for you? I don't remember exactly, but I think that VisualStudio's deployment cycle was quite plain:
rebuild
remove/uninstall old app from device -- so probably purges isolatedstorage
install new app onto device
So, maybe that's the cause? Hm.. on afterthought and re-reading your question again, you've said about running the app from the applist, so that rather is not the case. Be sure to check firstchance exceptions then!

Thanks to quetzalcoatl I found the solution:
I am storing all my files in the root Folder of my app. At the start I am then reading all my files (via a DataContractSerializer) and casting it to my model. Since it happens sometimes that my files get corrupt, I delete every file which throws a SerialzationException. But as I read every file, and since _ApplicationSettings is not castable to my model, I am deleting _ApplicationSettings automatically.... So I learned that the ApplicationSettings are,just a file in the root folder, which I am allowed to read and delete. So the quintessence is to never write into the root Folder.

Rename a running executable (exe) file [duplicate]

This question already has answers here:
Why does rename a loaded .net assembly work?
(3 answers)
Closed 5 years ago.
We are trying to push updates to multiple servers at once and my manager has found that it is possible to rename running .exe file. Using that knowledge he wants to rename a running exe and copy over a new version of said exe such that anyone running their in memory copy of foo.exe are fine and anybody who opens a shortcut pointing to foo.exe will get a new copy with updates applied.
I guess I need to clarify, He doesn't expect the old copy to magically update, he just expects them to keep running the old copy until they open the exe again, in which case it will then open the new one that has the name of the old one.
It sometimes throws an exception that the file is in use on his program but if he tries renaming it in a loop it will eventually succeed. On my machine I have yet to be able to get it to work even in a loop.
My first and main question is this: Is it ever acceptable to do this. Should renaming a running executable ever be a valid scenario?
Secondly, if it is a valid scenario then how could one reliably do this? Our current thoughts are try a bunch of times using File.Move (C#) to do a rename and if it doesn't work then write out to an error log so it can be handled manually.

An airplane mechanic and a surgeon meet in a bar. The mechanic says "you know, we have basically the same job. We take broken stuff out and put new, better parts in." The surgeon says "yeah, but you don't have to keep the plane flying as you're making the repairs!"
Trying to update an application by moving files while the application is running seems about as dangerous as trying to fix an airplane in flight. Possible? Sure. Greatly increased risk of catestrophic crash? Yep.
If the application you are updating is a managed application, consider using ClickOnce Deployment. That way, the next time someone runs the application, if there is a new version available it will be copied down and installed automatically. That's much more safe and pleasant than trying to mess with an application while its still running.

No, this is not acceptable. Do not do this. This is not a valid deployment mechanism. This should have been yours or his first clue:
It sometimes throws an exception that the file is in use on his program but if he tries renaming it in a loop it will eventually succeed.
And it won't work, anyway. His theory is quite wrong:
Using that knowledge he wants to rename a running exe and copy over a new version of said exe such that anyone running their in memory copy of foo.exe are fine and anybody who opens a shortcut pointing to foo.exe will get a new copy with updates applied.
Specifically, the copy in memory will not be automatically replaced with the new executable just because it has the same name. The reason that you're allowed to rename the executable in the first place is because the operating system is not using the file name to find the application. The original executable will still be loaded, and it will remain loaded until you explicitly unload it and load the new, modified executable.
Notice how even modern web browsers like Chrome and Firefox with their super fancy automatic, in the background, no one ever notices that they exist, updaters still have to close and relaunch the application in order to apply the updates.
Don't worry about shooting the messenger here. It's more likely that your customers and your tech support department will shoot you first.
See number 1.

In our organization, we solved the problem of Updates by having two release folders say EXE_A and EXE_B. We also have a release folder called EXE which only has links ALL of which points to either to EXE_A or EXE_B from which the user runs the applications.
When we publish a new version of the program, we publish it to the folder that is not referenced in the links and then update the links (EXE). In this way, you do not get into exceptions that users are holding the application / assemblies. Also if a user wants to run the updated version, all he need to do is close / re-execute the link in EXE folder.

If you use Windows Vista/Server2k8 or newer you could use mklink to create a symbolic link to the folder containing your application and start the application out of the "symblic linked folder" and then at the update create a new folder, e.g. "AppV2" and change the SymLink to that folder, so the next time the user restarts the application he starts it out of the new folder without noticing.
Renaming open files is ALWAYS a bad choice!
But in general I would think of a better deployment strategy anyway, because if you need to use such "hacks" it is always a messy situation. I don't know your application, but maybee ClickOnce would be a point to start, because you can configure it to check for updates on every start...