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CopyAsync method don`t replace existing file. UWP. Application-storage

Now I am working on edit operation in my app. So in edit operation there is an ability to change image and in the same time name of the file that keep image of the contact can not be renamed(during one session of operation image files will be changing but all this file will take same name).
And I used overload of CopyAsync method (docs to this method here) that as I have understand must to replace file to the existing file with the same name.
I get imageFile variable by FileOpenPicker. Code below runs every time I have choosed image by FileOpenPicker. And when I re-choose image at the result Image UI control show me previous chosen image. I expect that Image will view last image that I have choosed but this does not occurred.
public BitmapImage Image { set; get; }
//Copy of the file that saved in temporary storage
StorageFile fileForView = await imageFile.CopyAsync
(ApplicationData.Current.TemporaryFolder,
fileName,
NameCollisionOption.ReplaceExisting);
Image = new BitmapImage(new Uri(fileForView.Path));
Maybe I understand logic of CopyAsync method not correctly if I am in this case please show me how make my plan working with this method if it is possible. Otherwise offer your solution cause I have no idea now how to do this.
Also I tried to do this with CopyAndReplaceAsync method. But still no result. I do it in this way:
if (null != await ApplicationData.Current.TemporaryFolder.TryGetItemAsync(fileName))
{
StorageFile storageFile = await ApplicationData.Current.TemporaryFolder.GetFileAsync(fileName);
await storageFile.CopyAndReplaceAsync(imageFile);
}

I expect that Image will view last image that I have choosed but this does not occurred.
The above CopyAsync method is correct, and I have tested with the following code, it works well.
private async void ListOption_ItemClick(object sender, ItemClickEventArgs e)
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.Thumbnail;
openPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
openPicker.FileTypeFilter.Add(".jpg");
openPicker.FileTypeFilter.Add(".jpeg");
openPicker.FileTypeFilter.Add(".png");
StorageFile file = await openPicker.PickSingleFileAsync();
if (file != null)
{
StorageFile fileForView = await file.CopyAsync(ApplicationData.Current.TemporaryFolder, file.Name, NameCollisionOption.ReplaceExisting);
Image = new BitmapImage(new Uri(fileForView.Path));
TestImg.Source = Image;
}
else
{
}
}

how to get Bytes of a file for sending in UWP?

I'm a newbie in UWP and i want to open a file of any type and transmit the bytes of it to the reciever. forexample for a jpg file i wrote this code:
// Create FileOpenPicker instance
FileOpenPicker fileOpenPicker = new FileOpenPicker();
// Set SuggestedStartLocation
fileOpenPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
// Set ViewMode
fileOpenPicker.ViewMode = PickerViewMode.Thumbnail;
fileOpenPicker.FileTypeFilter.Clear();
fileOpenPicker.FileTypeFilter.Add(".jpg");
// Open FileOpenPicker
StorageFile file = await fileOpenPicker.PickSingleFileAsync();
byte[] bytesRead = File.ReadAllBytes(file.Path);
string Paths =
#"C:\\Users\zahraesm\Pictures\sample_reconstructed.jpg";
File.WriteAllBytes(Paths, bytesRead);
the two last lines are for writing the bytes into a file supposing in the receiver. However i keep getting the following exception:
System.InvalidOperationException: 'Synchronous operations should not be performed on the UI thread. Consider wrapping this method in Task.Run.'

Try this Code.
try {
FileOpenPicker openPicker = new FileOpenPicker {
ViewMode = PickerViewMode.Thumbnail,
SuggestedStartLocation = PickerLocationId.DocumentsLibrary,
FileTypeFilter = { ".jpg", ".jpeg", ".png" }
};
StorageFile file = await openPicker.PickSingleFileAsync();
if (file != null) {
using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read)) {
var reader = new Windows.Storage.Streams.DataReader(fileStream.GetInputStreamAt(0));
var LoadReader = await reader.LoadAsync((uint)fileStream.Size);
byte[] pixels = new byte[fileStream.Size];
reader.ReadBytes(pixels);
}
}
} catch (Exception ex) {
}

consider wrapping last operation in Task.Run()
await Task.Run(()=>{
byte[] bytesRead = File.ReadAllBytes(file.Path);
string Paths =
#"C:\\Users\zahraesm\Pictures\sample_reconstructed.jpg";
File.WriteAllBytes(Paths, bytesRead);
});

You should directly read the bytes from the StorageFile returned from your FilePicker, lest you end up with File permission errors in the future.
StorageFile file = await fileOpenPicker.PickSingleFileAsync();
var buffer = await FileIO.ReadBufferAsync(file);
byte[] bytes = System.Runtime.InteropServices.WindowsRuntime.WindowsRuntimeBufferExtensions.ToArray(buffer);
You should also use await FileIO.WriteBytesAsync(targetFile, myBytes) to write.
Unless you have broadFileSystemAccess in your package Manifest, you should generally avoid using the System.IO API unless you know your application explicitly has permission to access files in that area (i.e., your application's local storage), and instead use Windows.Storage API's
Check MSDN for File Access Permissions for UWP apps for more information on file permissions.
And if you do use System.IO, always perform the work on the background thread via await Task.Run(() => { ... }

Add photo from library to contact in wp8.1

In my windows phone application i'm trying to create a new contact and add an image that taken from the camera, but it didn't seems to work.
No matter what i do the photo is blank.
The only way it works for me is by using an image that i added in the assets folder (and not from camera), even trying to add the image to the local assets folder and then to upload it - don't work...
(there is no error, but the contact that was added don't have a photo).
await contact.SetDisplayPictureAsync(stream.AsStream().AsInputStream());
Here is my code:
when i get the selected image from store i save it to a bitmapImage and use its pixel buffer.
public async void AddContact(string displayName, string mobile, string email, byte[] data)
{
var store = await ContactStore.CreateOrOpenAsync();
var contact = new StoredContact(store)
{
DisplayName = displayName
};
var props = await contact.GetPropertiesAsync();
props.Add(KnownContactProperties.Email, email);
props.Add(KnownContactProperties.MobileTelephone, mobile);
using (var stream = bitmap.PixelBuffer.AsStream())
{
await contact.SetDisplayPictureAsync(stream.AsInputStream());
}
await contact.SaveAsync();
}
Please help!

I was doing the same to set profile picture in for contact and it was not working. But when I get IRandomAccessStream from storage file it worked here is what I am doing
var file = await folder.GetFileAsync("filename.jpeg"));
//Or you can get file direclty from localfolder
// var file = await ApplicationData.Current.LocalFolder.GetFileAsync("filename.jpeg");
using (Windows.Storage.Streams.IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
{
await contact.SetDisplayPictureAsync(fileStream);
}
await contact.SaveAsync();
Edit
How to Save picture to local storage using media capture.
ImageEncodingProperties imgFormat = ImageEncodingProperties.CreateJpeg();
//Save file to local storage
StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync(
"MyPhoto.jpg", CreationCollisionOption.ReplaceExisting);
await mediaCapture.CapturePhotoToStorageFileAsync(imgFormat, file);
Once the image is saved in local storage you can get that image from me first example
Edit 2
If you are using File open picker you can try this.
public async void ContinueFileOpenPicker(Windows.ApplicationModel.Activation.FileOpenPickerContinuationEventArgs args)
{
if (args.Files.Count > 0)
{
var filePath = args.Files[0].Path;
StorageFile file = await Windows.Storage.StorageFile.GetFileFromPathAsync(filePath);
using (Windows.Storage.Streams.IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
{
await contact.SetDisplayPictureAsync(fileStream);
}
}

System.Runtime.InteropServices.COMException occurred in mscorlib.ni.dll but was not handled in user code

I am developing a windows application in 8.1 and I am getting a following error.
my application includes a procedure in which I will be moving a file from local storage to SD card.
My code is as follows
namespace MoveFile
{
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
this.NavigationCacheMode = NavigationCacheMode.Required;
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
}
private async void btnCreateFolder_Click(object sender, RoutedEventArgs e)
{
await ReadFile();
//Error is showing here
**await WriteToFile();
}
public async Task WriteToFile()
{
// Get the text data from the textbox.
byte[] fileBytes = System.Text.Encoding.UTF8.GetBytes(this.txtSafakCount.Text.ToCharArray());
//I got the error in this line.....showing interopservice exception
** StorageFolder knownFolder = await KnownFolders.RemovableDevices.CreateFolderAsync("bdfbdfb", CreationCollisionOption.ReplaceExisting);
StorageFolder sdCard = (await knownFolder.GetFoldersAsync()).FirstOrDefault();
// Create a new file named DataFile.txt.
var file = await sdCard.CreateFileAsync("kaaaaammmmfewfwmHoJa.txt", CreationCollisionOption.ReplaceExisting);
// Write the data from the textbox.
using (var s = await file.OpenStreamForWriteAsync())
{
s.Write(fileBytes, 0, fileBytes.Length);
}
}
public async Task ReadFile()
{
// Get the local folder.
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder;
if (local != null)
{
// Get the DataFolder folder.
var dataFolder = await local.GetFolderAsync("DataFolder");
// Get the file.
await dataFolder.CreateFileAsync("DataFile.txt", CreationCollisionOption.ReplaceExisting);
var file = await dataFolder.OpenStreamForReadAsync("DataFile.txt");
// Read the data.
using (StreamReader streamReader = new StreamReader(file))
{
this.txtSafakCount.Text = streamReader.ReadToEnd();
}
}
}
}
}
I want to know why this exception occurred and how it can be resolved.
Thanks in advance.

You are doing it wrong - first you should get SD card, then create folder. As the name KnownFolders.RemovableDevices says devices (not single device) - so you get the first of them as SD card (note that Universal Apps are not only for phones). So the working code can look like this:
// first get the SD card
StorageFolder sdCard = (await KnownFolders.RemovableDevices.GetFoldersAsync()).FirstOrDefault();
// then perform some actions - create folders, files ...
StorageFolder myFolder = await sdCard.CreateFolderAsync("bdfbdfb", CreationCollisionOption.ReplaceExisting);
Note also that you also need to add Capabilities in package.appxmanifest file, and Declarations if you want to use files (File Type Associations).
You will also find more help at MSDN.

how to copy image from filepiker to app folder windows store apps

this is the code of file picker
i need to copy the image that user open it to app folder.
any one can help me please
private async void Button_Click(object sender, RoutedEventArgs e)
{
if (Windows.UI.ViewManagement.ApplicationView.Value != Windows.UI.ViewManagement.ApplicationViewState.Snapped ||
Windows.UI.ViewManagement.ApplicationView.TryUnsnap() == true)
{
Windows.Storage.Pickers.FileOpenPicker openPicker = new Windows.Storage.Pickers.FileOpenPicker();
openPicker.SuggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.PicturesLibrary;
openPicker.ViewMode = Windows.Storage.Pickers.PickerViewMode.Thumbnail;
// Filter to include a sample subset of file types.
openPicker.FileTypeFilter.Clear();
openPicker.FileTypeFilter.Add(".bmp");
openPicker.FileTypeFilter.Add(".png");
openPicker.FileTypeFilter.Add(".jpeg");
openPicker.FileTypeFilter.Add(".jpg");
// Open the file picker.
Windows.Storage.StorageFile file = await openPicker.PickSingleFileAsync();
// file is null if user cancels the file picker.
if (file != null)
{
// Open a stream for the selected file.
Windows.Storage.Streams.IRandomAccessStream fileStream =
await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
// Set the image source to the selected bitmap.`
Windows.UI.Xaml.Media.Imaging.BitmapImage bitmapImage =
new Windows.UI.Xaml.Media.Imaging.BitmapImage();
bitmapImage.SetSource(fileStream);
img.Source = bitmapImage;
this.DataContext = file;
}
}
}
thanks

Use StorageFile.CopyAsync, that is, file.CopyAsync. The first argument is the destination StorageFolder, e.g. Windows.Storage.ApplicationData.Current.LocalFolder if you wanted to copy to appdata; otherwise you'd need to create a folder or get one from a picker separately.
You might, for example, have the user choose a default folder with the file picker (configured for folders). Just be sure to save that StorageFolder in the [Windows.Storage.AccessCache][2] to preserve programmatic access for future use.