/// <summary>
/// Gets a folder, given its path. Returns null if the folder does not exist.
/// </summary>
/// <param name="path">The path to a folder, as returned from the <see cref="IFolder.Path"/> property.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A folder for the specified path, or null if it does not exist.</returns>
public async Task <IFolder> GetFolderFromPathAsync(string path, CancellationToken cancellationToken = default(CancellationToken))
{
Ensure.NotNullOrEmpty(path, nameof(path));
await AsynchronityUtilities.SwitchOffMainThreadAsync(cancellationToken);
return(Directory.Exists(path) ? new Folder(path, true) : null);
}
/// <summary>
/// Gets a file, given its path. Returns null if the file does not exist.
/// </summary>
/// <param name="path">The path to a file, as returned from the <see cref="IFile.Path"/> property.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A file for the given path, or null if it does not exist.</returns>
public async Task <IFile> GetFileFromPathAsync(string path, CancellationToken cancellationToken = default(CancellationToken))
{
Ensure.NotNullOrEmpty(path, nameof(path));
await AsynchronityUtilities.SwitchOffMainThreadAsync(cancellationToken);
return(System.IO.File.Exists(path) ? new File(path) : null);
}
/// <summary>
/// Deletes the file.
/// </summary>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
/// <returns>A task which will complete after the file is deleted.</returns>
public async Task DeleteAsync(CancellationToken cancellationToken = default(CancellationToken))
{
await AsynchronityUtilities.SwitchOffMainThreadAsync(cancellationToken);
if (!System.IO.File.Exists(Path))
{
throw new System.IO.FileNotFoundException("File does not exist: " + Path);
}
System.IO.File.Delete(Path);
}
/// <summary>
/// Opens the file.
/// </summary>
/// <param name="fileAccess">Specifies whether the file should be opened in read-only or read/write mode.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A <see cref="Stream"/> which can be used to read from or write to the file.</returns>
public async Task <Stream> OpenAsync(FileAccess fileAccess, CancellationToken cancellationToken = default(CancellationToken))
{
await AsynchronityUtilities.SwitchOffMainThreadAsync(cancellationToken);
switch (fileAccess)
{
case FileAccess.Read:
return(System.IO.File.OpenRead(Path));
case FileAccess.ReadWrite:
return(System.IO.File.Open(Path, FileMode.Open, FileAccess.ReadWrite));
}
throw new ArgumentException("Unrecognized FileAccess value: " + fileAccess);
}
/// <summary>
/// Moves a file.
/// </summary>
/// <param name="newPath">The new full path of the file.</param>
/// <param name="collisionOption">How to deal with collisions with existing files.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A task which will complete after the file is moved.</returns>
public async Task MoveAsync(string newPath, NameCollisionOption collisionOption = NameCollisionOption.ReplaceExisting, CancellationToken cancellationToken = default(CancellationToken))
{
Ensure.NotNullOrEmpty(newPath, nameof(newPath));
await AsynchronityUtilities.SwitchOffMainThreadAsync(cancellationToken);
string newDirectory = System.IO.Path.GetDirectoryName(newPath);
string newName = System.IO.Path.GetFileName(newPath);
for (int counter = 1; ; counter++)
{
cancellationToken.ThrowIfCancellationRequested();
string candidateName = counter > 1 ? $"{System.IO.Path.GetFileNameWithoutExtension(newName)} ({counter}){System.IO.Path.GetExtension(newName)}" : newName;
string candidatePath = System.IO.Path.Combine(newDirectory, candidateName);
if (System.IO.File.Exists(candidatePath))
{
switch (collisionOption)
{
case NameCollisionOption.FailIfExists:
throw new IOException("File already exists.");
case NameCollisionOption.GenerateUniqueName:
continue; // try again with a new name.
case NameCollisionOption.ReplaceExisting:
System.IO.File.Delete(candidatePath);
break;
}
}
System.IO.File.Move(Path, Path = candidatePath);
Name = candidateName;
return;
}
}