Develop Reference

Add image source from StorageFile UWP

I'm trying to add image source from Storage Folder. First I capture photo and save it to the Storage Folder
Windows.Storage.StorageFolder storageFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
private async void btnPhoto_Click(object sender, RoutedEventArgs e)
{
// Create the file that we're going to save the photo to.
var file = await storageFolder.CreateFileAsync("sample.jpg", CreationCollisionOption.GenerateUniqueName);
// Update the file with the contents of the photograph.
await _mediaCapture.CapturePhotoToStorageFileAsync(ImageEncodingProperties.CreateJpeg(), file);
}
At the next Page I should get the photo from cache, but I have an exception, when I'm creating sampleFile
public async void GetImage()
{
string filename = "sample.jpg";
Windows.Storage.StorageFile sampleFile =
await Windows.Storage.KnownFolders.DocumentsLibrary.GetFileAsync(filename); // Here I have exception {"Access is denied.\r\n"} System.UnauthoriziedAccessException
BitmapImage img = new BitmapImage();
img = await LoadImage(sampleFile);
image1.Source = img;
}
private static async Task<BitmapImage> LoadImage(StorageFile file)
{
BitmapImage bitmapImage = new BitmapImage();
FileRandomAccessStream stream = (FileRandomAccessStream)await file.OpenAsync(FileAccessMode.Read);
bitmapImage.SetSource(stream);
return bitmapImage;
}
What I'm doing wrong? And how can I get access to Storage Folder?

You can't access the document library unless the user allows you to do that. You can specify document library access in the manifest, but only for certain files, and such app will probably never be published in the Windows Store unless it REALLY requires that access as stated by Microsoft. As you are using .jpg files you have Pictures library for that, and you can specify it in the manifest and everything will work just fine.
Otherwise you get access by file picker, storing the token to recall it later.

Download Video File via video URL in windows phone 8.1 C#

I have tried to download video file from video URL. Video file created but downloading does not happen here. just 57KB file generate. My code is here.
public async void DownloadTrack(Uri SongUri, string fileName)
{
using (HttpClient httpClient = new HttpClient())
{
var data = await httpClient.GetByteArrayAsync(SongUri);
StorageFolder storageFolder = KnownFolders.VideosLibrary;
var file = await storageFolder.CreateFileAsync(fileName, CreationCollisionOption.GenerateUniqueName);
///////////////////
using (var targetStream = await file.OpenAsync(FileAccessMode.ReadWrite))
{
await targetStream.AsStreamForWrite().WriteAsync(data, 0, data.Length);
await targetStream.FlushAsync();
}
}
}
Here video file creates but does not file download. I want to download file. I searched much about this. here is accepted Stackoverflow answer link but this also does the same. Example
can you please provide any better solution.

Unzipping files in WP8.1 Using SharpZipper

I am trying to use SharpZip.unzipper for my windows phone 8.1. However it is not reading some of the code. Since i am fairly new to windows phone development please let me know the alternatives of following code for WP8.1
using System.Windows.Resources;
public Stream GetFileStream(string filename)
{
if (fileEntries == null)
fileEntries = ParseCentralDirectory(); //We need to do this in case the zip is in a format Silverligth doesn't like
long position = this.stream.Position;
this.stream.Seek(0, SeekOrigin.Begin);
Uri fileUri = new Uri(filename, UriKind.Relative);
StreamResourceInfo info = new StreamResourceInfo(this.stream, null);
StreamResourceInfo stream = System.Windows.Application.GetResourceStream(info, fileUri);
this.stream.Position = position;
if (stream != null)
return stream.Stream;
return null;
}
Windows.Resources seems missing
I can't call StreamResourceInfo, System.Windows.Application
I have tried using App. but there is no function for GetResourceSteam
I am not sure what to do here

There are quite a few differences between WP8.1 runtime and WP8.1 Silverlight.
The code sample that you have will run on WP8.0 SL and WP8.1 SL.
It looks like you created a Windows Phone 8.1 runtime project. There is no System.Windows.Application.GetResourceStream()
Either convert it to a compatible 8.1 runtime stream or recreate your project to target Silverlight instead.
// sample
private async void ZipLibraryTest()
{
// create the full path
string zip = Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, "filename.zip");
// create the storage file with the file name
StorageFile sf = await StorageFile.GetFileFromPathAsync(zip);
// create the IO Stream
using (System.IO.Stream output = await sf.OpenStreamForWriteAsync())
{
// open the zip file for writing, use the stream from the file
ZipFile zf = ZipFile.Create(output);
// rest of your code
// ...
// ...
// close the zip file
zf.Close();
}
}

Write byte array to storage file in windows phone

I'm using Visual studio 2012, c#, silverlight, windows phone 8 app.
We get our data from a webservice, and through the webservice we get a picture that is an base64 string.
I convert it to a byte array, and now I want to save it so the Storage of the windows phone, using a memory stream? I don't know if it is the right approach. I don't want to save it to isolated storage, just the local folder because I want to show the picture after a person tapped on the link.
this is what I have so far.
byte[] ImageArray;
var image = Attachmentlist.Attachment.ToString();
imagename = Attachmentlist.FileName.ToString();
ImageArray = Convert.FromBase64String(image.ToString());
StorageFolder myfolder = Windows.Storage.ApplicationData.Current.LocalFolder;
await myfolder.CreateFileAsync(imagename.ToString());
StorageFile myfile = await myfolder.GetFileAsync(imagename.ToString());
MemoryStream ms = new MemoryStream();
so after I have initialized the memory stream how do I take the byte array and write it to the storage file, and after that retrieve it again?

To write file to disc try this code:
StorageFile sampleFile = await myfolder.CreateFileAsync(imagename.ToString(),
CreateCollisionOption.ReplaceExisting);
await FileIO.WriteBytesAsync(sampleFile, ImageArray);
Memory stream creates stream that writes in memory so it is not applicable to this problem.

StorageFolder folder = ApplicationData.Current.LocalFolder;
StorageFile imageFile = await folder.CreateFileAsync("Sample.png", CreationCollisionOption.ReplaceExisting);
using (IRandomAccessStream fileStream = await imageFile.OpenAsync(FileAccessMode.ReadWrite))
{
using (IOutputStream outputStream = fileStream.GetOutputStreamAt(0))
{
using (DataWriter dataWriter = new DataWriter(outputStream))
{
dataWriter.WriteBytes(imageBuffer);
await dataWriter.StoreAsync();
dataWriter.DetachStream();
}
//await outputStream.FlushAsync();
}
//await fileStream.FlushAsync();
}

Download and Save image in Pictures Library through Windows 8 Metro XAML App

I am trying to develop a simple Windows 8 Metro app which simply downloads an image file from a given URL (say http://sample.com/foo.jpg) and then save it to Pictures Library.
I have an image control in the UI to display the downloaded image.
I'm also facing difficulty in setting the image source for the image control to the newly downloaded image (actually I'm not even able to download it).
Also, is it possible to store the image file in a particular folder in the Pictures library (if it doesn't exist, then the app should create it)?
I'm really stuck here.
Please help me.

Here's some rough code that I believe accomplishes what you want. It assumes you have two image controls (Image1 and Image2) and that you have the Pictures Library capability checked in the manifest. Take a look at the XAML images sample as well
Uri uri = new Uri("http://www.picsimages.net/photo/lebron-james/lebron-james_1312647633.jpg");
var fileName = Guid.NewGuid().ToString() + ".jpg";
// download pic
var bitmapImage = new BitmapImage();
var httpClient = new HttpClient();
var httpResponse = await httpClient.GetAsync(uri);
byte[] b = await httpResponse.Content.ReadAsByteArrayAsync();
// create a new in memory stream and datawriter
using (var stream = new InMemoryRandomAccessStream())
{
using (DataWriter dw = new DataWriter(stream))
{
// write the raw bytes and store
dw.WriteBytes(b);
await dw.StoreAsync();
// set the image source
stream.Seek(0);
bitmapImage.SetSource(stream);
// set image in first control
Image1.Source = bitmapImage;
// write to pictures library
var storageFile = await KnownFolders.PicturesLibrary.CreateFileAsync(
fileName,
CreationCollisionOption.ReplaceExisting);
using (var storageStream = await storageFile.OpenAsync(FileAccessMode.ReadWrite))
{
await RandomAccessStream.CopyAndCloseAsync(stream.GetInputStreamAt(0), storageStream.GetOutputStreamAt(0));
}
}
}
// read from pictures library
var pictureFile = await KnownFolders.PicturesLibrary.GetFileAsync(fileName);
using ( var pictureStream = await pictureFile.OpenAsync(FileAccessMode.Read) )
{
bitmapImage.SetSource(pictureStream);
}
Image2.Source = bitmapImage;
}