/// <summary>
/// Checks whether a folder or file exists at the given location.
/// </summary>
/// <param name="name">The name of the file or folder to check for.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>
/// A task whose result is the result of the existence check.
/// </returns>
public async Task <ExistenceCheckResult> CheckExistsAsync(string name, CancellationToken cancellationToken)
{
Requires.NotNullOrEmpty(name, "name");
// WinRT does not expose an Exists method, so we have to
// try accessing the entity to see if it succeeds.
// We could code this up with a catch block, but that means
// that a file existence check requires first chance exceptions
// are thrown and caught, which *can* slow the app down,
// and also bugs the developer who is debugging the app.
// So we just avoid all exceptions being *thrown*
// by checking for exception objects carefully.
var result = await _wrappedFolder.GetItemAsync(name).AsTaskNoThrow(cancellationToken);
if (result.IsFaulted)
{
if (result.Exception.InnerException is FileNotFoundException)
{
return(ExistenceCheckResult.NotFound);
}
else
{
// rethrow unexpected exceptions.
result.GetAwaiter().GetResult();
throw result.Exception; // shouldn't reach here anyway.
}
}
else if (result.IsCanceled)
{
throw new OperationCanceledException();
}
else
{
Windows.Storage.IStorageItem storageItem = result.Result;
if (storageItem.IsOfType(StorageItemTypes.File))
{
return(ExistenceCheckResult.FileExists);
}
else if (storageItem.IsOfType(StorageItemTypes.Folder))
{
return(ExistenceCheckResult.FolderExists);
}
else
{
return(ExistenceCheckResult.NotFound);
}
}
}
public async void PopulateRecentsList()
{
var mostRecentlyUsed = Windows.Storage.AccessCache.StorageApplicationPermissions.MostRecentlyUsedList;
BitmapImage ItemImage = new BitmapImage();
string ItemPath = null;
string ItemName;
StorageItemTypes ItemType;
Visibility ItemFolderImgVis;
Visibility ItemEmptyImgVis;
Visibility ItemFileIconVis;
if (mostRecentlyUsed.Entries.Count == 0)
{
Empty.Visibility = Visibility.Visible;
}
else
{
Empty.Visibility = Visibility.Collapsed;
}
foreach (Windows.Storage.AccessCache.AccessListEntry entry in mostRecentlyUsed.Entries)
{
string mruToken = entry.Token;
try
{
Windows.Storage.IStorageItem item = await mostRecentlyUsed.GetItemAsync(mruToken);
if (item.IsOfType(StorageItemTypes.File))
{
ItemName = item.Name;
ItemPath = item.Path;
ItemType = StorageItemTypes.File;
ItemImage = new BitmapImage();
StorageFile file = await StorageFile.GetFileFromPathAsync(ItemPath);
var thumbnail = await file.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode.ListView, 30, Windows.Storage.FileProperties.ThumbnailOptions.ResizeThumbnail);
if (thumbnail == null)
{
ItemEmptyImgVis = Visibility.Visible;
}
else
{
await ItemImage.SetSourceAsync(thumbnail.CloneStream());
ItemEmptyImgVis = Visibility.Collapsed;
}
ItemFolderImgVis = Visibility.Collapsed;
ItemFileIconVis = Visibility.Visible;
recentItemsCollection.Add(new RecentItem()
{
path = ItemPath, name = ItemName, type = ItemType, FolderImg = ItemFolderImgVis, EmptyImgVis = ItemEmptyImgVis, FileImg = ItemImage, FileIconVis = ItemFileIconVis
});
}
}
catch (System.IO.FileNotFoundException)
{
mostRecentlyUsed.Remove(mruToken);
}
catch (UnauthorizedAccessException)
{
// Skip item until consent is provided
}
}
}
