I am trying to read the chrome bookmark file within a windows 8 app. Problem is I am getting the 'System.UnauthorizedAccessException' exception. So basically you have to register a file type association in the app manifest but the file has no extension.
File: C:\Users\<User>\AppData\Local\Google\Chrome\User Data\Default\Bookmarks
Is this even possible in windows 8 apps?
UPDATE
Here is my file access code:
public async Task<string> ReadFile(string filename)
{
if (await FileExists(filename))
{
var file = await Windows.ApplicationModel.Package.Current.InstalledLocation.GetFileAsync(filename);
var stream = await file.OpenReadAsync();
var reader = new StreamReader(stream.AsStream());
return await reader.ReadToEndAsync();
}
else return string.Empty;
}
Windows 8 app cannot access any random file system location. It can only access
Application Folder (which is specific to your app)
Common Folders like My Pictures, My Video and similar
See this article for complete details
A workaround is to use the file picker. This allows the end user to manually select files on the filesystem. Once you have the FileStorage object from the file picker, you can then open and read the file.
Optionally, you can then save the StorageFile for later use, meaning that your app can access the file later, without the end user having to select the file again.
More info on MSDN:
File Open Picker
How to track recently used files and folders
Related
I have built a app that read a config file and load a dictionary based on the xml.
What I want is to not need to add that file to the program. Instead I want to be able to upload to the pi3 and then tell the program to refresh and read the file I uploaded. It loads the file included with the code to an obscure folder.
How can I upload and specify the path in my code to a folder that is easier to get to.
Thanks in advance
Use the Windows.Storage namespace and following the below code for creating,accessing and other operations like these in Folder and Files on UWP.
//Get Installation Folder for current application
StorageFolder rootFolder = ApplicationData.Current.LocalFolder;
//Create a folder in the root folder of app if not exist and open if exist.
StorageFolder Folder = await rootFolder.CreateFolderAsync(yourFolderName, CreationCollisionOption.OpenIfExists);
//Craete a file in your folder if not exist and replace it with new file if exist
StorageFile sampleFile = await Folder.CreateFileAsync("samplefile.xml", CreationCollisionOption.ReplaceExisting);
//Create your text and write it on your configuaration file
string yourText = "Your Sample Text or Configuration";
await Windows.Storage.FileIO.WriteTextAsync(sampleFile, yourText);
After that you can get access the file again read your configuration value from that form ReadTextAsync method.
//Read data from file
await Windows.Storage.FileIO.ReadTextAsync(sampleFile);
I'm writing a cross platform application in xamarin, for Android and iOS, and I need to save some text files to local storage. I'm using PCLstorage, but whenever I mouse over any PCLStorage code, it says "MyApplication.Android: available, MyApplication.iOS not available". How can I use PCLStorage to store files on both platforms? Or is there another way I can do this? Here's an example of some of my code:
public async Task CreateRealFileAsync(string filename, string filebody)
{
// get hold of the file system
IFolder rootFolder = FileSystem.Current.LocalStorage;
// create a folder, if one does not exist already
IFolder folder = await rootFolder.CreateFolderAsync("DadAppFiles", CreationCollisionOption.OpenIfExists);
// create a file, overwriting any existing file
IFile file = await folder.CreateFileAsync(filename, CreationCollisionOption.ReplaceExisting);
// populate the file with some text
await file.WriteAllTextAsync(filebody);
}
What I need to do:
Save an image file to an exact, specific location when the app is run (Let's say "Z:\test\photo.jpeg").
Additional wanted functionality:
1) Overwrite the file ''Z:\test\photo.jpeg' if it already exists.
2) Skip the write, if the folder 'Z:\test\' doesn't exist.
What I've already tried:
using Windows.Media.Capture.UI;
using Windows.Storage;
CameraCaptureUI camera = new CameraCaptureUI();
StorageFile photo = await camera.CaptureFileAsync(CameraCaptureUIMode.Photo);
if (photo != null)
{
var targetFile = await ApplicationData.Current.LocalFolder.CreateFileAsync("photo.jpeg", CreationCollisionOption.ReplaceExisting);
if (targetFile != null)
{
await targetFile.DeleteAsync();
await photo.MoveAndReplaceAsync(targetFile);
}
}
Question:
Is there a way to get the variable 'targetFile' to point to a particular location, eg. "Z:\test\photo.jpeg"?
I don't want to use local app data folder, pictures folder, or anything like that. It needs to be this particular location.
Univeral Apps are sandboxed and can only access their on storage folders.
You can grant access to other files using FileOpenPicker or FolderPicker, but you won't have control about what file the user picks for you to write into.
This means you have to make your user pick that exact file for you to store at, otherwise your app can't access that location.
Here's an overview on accessible file locations for UWP apps on MSDN.
I am creating an app that is tracking GPS data (latitude, longitude, altitude). So far I've managed to create a listbox that gets an extra line everytime another set of coordinates is made.
I tried writing it to file with this function.
private async Task WriteToFile()
{
string ResultString = string.Join("\n", locationData.ToArray());
byte[] fileBytes = System.Text.Encoding.UTF8.GetBytes(ResultString);
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder;
var dataFolder = await local.CreateFolderAsync("DataFolder", CreationCollisionOption.OpenIfExists);
var file = await dataFolder.CreateFileAsync("DataFile.txt", CreationCollisionOption.ReplaceExisting);
using (var s = await file.OpenStreamForWriteAsync())
{
s.Write(fileBytes, 0, fileBytes.Length);
}
}
I can read this file, but I can't view this "DataFile.txt" anywhere in Files app.
I tried using WP Power Tools, but it doesn't work with 8.1, I am unable to update Visual Studio 2013 in order to get ISExplorer.exe working and
IsoStoreSpy keeps crashing everytime I try to connect my Lumia 620.
But all of this looks too complitated to me. Is there any other way of getting this .txt file without messing with IsolatedStorage? I feel like I'm missing out on something so simple here, I just can't believe that such basic thing as writing output to .txt, that can be later used by PC, couldn't be available.
You're storing the file in your app's local storage (Windows.Storage.ApplicationData.Current.LocalFolder), which is the same as Isolated Storage.
The Files app can see only public locations not app-specific locations.
There are several ways your app can share this file more globally:
Use the share contract to let the user share the file to wherever they'd like (OneNote, Email, etc.). See Sharing and exchanging data
Let the user choose where to save the file with a FileSavePicker. See How to save files through file pickers
Save the file on the SD card. See Access the SD card in Windows Phone apps.
Save the file to the user's OneDrive. See Guidelines for accessing OneDrive from an app
Save to a RoamingFolder so the file can be read by the same app on a Windows PC, which can then export using similar methods (especially a file picker) but on the desktop device. See Quickstart: Roaming app data
I am working with Visual Studio ultimate 2013 and using windows store apps.
My visual studio project folder "History"(name of the current project) is located in D:Academic folder.
I have created text file in the History project folder.
And I want to print the details in text file to a text block.
This code works.
According to this, the location of the text file is created in Local Folder.
public History()
{
this.InitializeComponent();
StorageFolder = ApplicationData.Current.LocalFolder;
}
private async void Button_Click(object sender, RoutedEventArgs e)
{
ReadText();
}
async void ReadText()
{
StorageFile file = await StorageFolder.GetFileAsync(filename);
ghij.Text = await FileIO.ReadTextAsync(file)
}
private void Write_click(object sender, RoutedEventArgs e)
{
WriteText();
cdef.Text = "";
}
async void WriteText()
{
StorageFile file = await StorageFolder.CreateFileAsync(filename, CreationCollisionOption.ReplaceExisting);
await FileIO.WriteTextAsync(file, cdef.Text);
}
In my case I don't want to create and write a file,but to READ an already created file which is located in D:\Academic:\History folder.
So how can I change the path to access the text file.
Please help.
Windows store apps don't have full access to the file system. You can give them access however to specific places like the Documents through the so called capabilities. You can also save and restore content from local storage.
You don't have direct access in Windows Store Apps. FilePicker class would serve you most of the time to open a file but if you want a programmatic access to a file then you need to declare appropriate capabilities in your package manifest.
And yes you want to access documents library, in that case you have to declare documents library capability in your package manifest.
From MSDN :
The file picker provides a robust UI mechanism that enables users to open files for use with an app. Declare the documentsLibrary capability only when you cannot use the file picker.
NOTE : Documents library only gives access to file formats filtered by the types declared in the manifest.
For eg. For example, if a DOC reader app declared a .doc file type association, it can open .doc files in Documents, but not other types of files.
You can't use the Documents library in a Windows Phone Store app.
You can't publish a Windows Phone Store app that specifies the documentsLibrary capability to the Windows Phone Store. The Store blocks the publishing of the app.
You can refer MSDN Arcticle on Manifest capabilties.