Develop Reference

how to create sqlite database in windows store app located at a specific folder

Need help, I can't seem to access any other .sqlite database if its not located in the apps localfolder. Every tutorial I look at they always use
Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, "Example.sqlite");
I tried this:
const string testing = #"C:\Users\***\AppData\Local\Packages\*************\LocalState";
this.DBPath = Path.Combine(testing, "Example.sqlite");
using (var db = new SQLite.SQLiteConnection(this.DBPath))
{
db.CreateTable<Customer>();
}
and it worked. but when I change it to:
const string testing = #"C:\Databases";
It can't open the database even if I copied the database from the local folder of the app.
Any suggestions ? I'm still trying to learn.

You can't access the C: drive for windows store apps. It's part of the store's sandbox. Each app is limited to which files and folders can be viewed. If you have a local database file you need to access, define the file as content in your app and access it using the path "ms-appx:///..."

use file picker to select which folder you want to save the db file.
refer this article:
http://msdn.microsoft.com/en-us/library/windows/apps/hh967755.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-1

How to zip a database file in winrt app?

I have a sqlite database file "test.db".
I want to zip this file through C# code.
But when I am trying to do this, I am getting "Access is denied" exception.
Here is the code that I am using :
byte[] buffer = WindowsRuntimeBufferExtensions.ToArray(await FileIO.ReadBufferAsync(fileToCompress));
ZipArchiveEntry entry = zipArchive.CreateEntry(fileToCompress.Name);
using (Stream entryStream = entry.Open())
{
await entryStream.WriteAsync(buffer, 0, buffer.Length);
}
Can any one tell how I can zip a database file in winrt app through C# code ?

I'm away from my pc here so I cannot try this but:
Windows RT apps cannot access files in the system outside the windows-user folders (Videos, Music, Documents, Downloads, Pictures and USB units) from code. This is only possible by using a file picker (this way, the user is responsible for the file selection).
If you try to do so from code, you get an exception.
Have you tried that piece of code having the "test.db" file inside the current user "Documents" folder?
The other idea that comes to mind, is to check that the Database is not opened and has been detached from your DBA.

Folder to store data files locally in WPF application

I currently have the code below in my WPF application which does exactly what I want it to do, however, upon publishing this it won't necessarily be able to access these folder locations as they won't be pointing to the correct directory nor will the folders exist.
I was hoping somebody might be able to tell me what is the best way to save something into a local folder?
Whether it's inside the application folder itself or not is of no issue either.
The code I'm currently using for the writing of the file:
using (Stream stream = File.Open(#"..\..\Templates\data.bin", FileMode.Create))
{
BinaryFormatter bin = new BinaryFormatter();
bin.Serialize(stream, templateList);
}
The code I'm currently using for the loading of the file:
using (Stream stream = File.Open(#"..\..\Templates\data.bin", FileMode.Open))
{
BinaryFormatter bin = new BinaryFormatter();
templateList = (List<Template>)bin.Deserialize(stream);
}

You could use System.Environment.SpecialFolder.LocalApplicationData to store application specific data:
using System;
class Sample
{
public static void Main()
{
Console.WriteLine("GetFolderPath: {0}",
Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData));
}
}
Ref: http://msdn.microsoft.com/en-us/library/system.environment.specialfolder.aspx

You can use Environment.SpecialFolder to find an appropriate place to put files (for example, ApplicationData would be a good place to start). If you only need a temp file, you can use Path.GetTempFileName to create one.
Edit: One last note. Storing stuff in the application folder itself can be a giant pain. Usually the application folder is created with the admin account during the installation so your app won't be able to write to it while running on a user account.

Opening up PDFs and other documents from Silverlight out of browser

I'm having a little problem figuring out the best way to open up a file that I have stored in a database. The file is being stored as a byte array in a nvarbinary field in the database. Currently when I want to open up a file I use an ASP.NET webpage that I pass a variable to and write the file stream to the page. This works fine when using the in browser version of the Silverlight application, but when out of browser I cannot invoke a browser window to open because I don't have access to dom.
How can I open the bytearray from Silvelright without invoking a browser window? I'm able to pass the bytearray and file type to the Silverlight app no problem. I just don't know how to display it once I have it there..
Thanks!

If you are targeting windows (with full trust enabled, and not mac), you can do this out-of-browser by first writing the file to disk (either in isolated storage or in My Documents), then using a WScript.Shell COM object to have the OS open the file.
After you have saved the byte stream to a file and have the file location, you can do:
using (dynamic shell = AutomationFactory.CreateObject("WScript.Shell"))
{
shell.Run(fileLocation); //works similar to start -> run -> filename
}
If you want to leverage your existing ASP page, you can pass its URL to shell.Run and the OS will use the user's default browser to open that page.
On a mac, the best you could do is save the file to their user directory, and have them manually navigate there with finder and double-click it.

Silverlight and reading local directory

Im trying to clone facebook image uploader which is built in java. But I would like to use silverlight so Im wondering if I can somehow read local directory.
If I have this running an some remote server I can easily read the content of that server as I have C# as backend. But Im not sure how could I read certain directory of the user which is using silverlight application.
Any ideas if this is possible or not?

It's possible to read file "blindly" using OpenFileDialog. Blindly means you can let the user point the dialog to the file so Silverlight can read its content but it can't tell where the file is located.
Example:
var fileDialog = new OpenFileDialog();
var dialog = fileDialog.ShowDialog();
if (dialog.HasValue && dialog.Value)
{
byte[] bytes;
using (var fileReader = fileDialog.File.OpenRead())
{
bytes = new byte[fileReader.Length];
fileReader.Read(bytes, 0, (int) fileReader.Length);
}
}
The access to the file system is limited for security. Some access (blind as well) can be done using Isolated Storage where you can store data and access later.