/// <summary>
/// Opens this alternate data stream.
/// </summary>
/// <param name="mode">
/// A <see cref="FileMode"/> value that specifies whether a stream is created if one does not exist,
/// and determines whether the contents of existing streams are retained or overwritten.
/// </param>
/// <param name="access">
/// A <see cref="FileAccess"/> value that specifies the operations that can be performed on the stream.
/// </param>
/// <param name="share">
/// A <see cref="FileShare"/> value specifying the type of access other threads have to the file.
/// </param>
/// <param name="bufferSize">
/// The size of the buffer to use.
/// </param>
/// <param name="useAsync">
/// <see langword="true"/> to enable async-IO;
/// otherwise, <see langword="false"/>.
/// </param>
/// <returns>
/// A <see cref="FileStream"/> for this alternate data stream.
/// </returns>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="bufferSize"/> is less than or equal to zero.
/// </exception>
/// <exception cref="SecurityException">
/// The caller does not have the required permission.
/// </exception>
/// <exception cref="UnauthorizedAccessException">
/// The caller does not have the required permission, or the file is read-only.
/// </exception>
/// <exception cref="IOException">
/// The specified file is in use.
/// </exception>
/// <exception cref="ArgumentException">
/// The path of the stream is invalid.
/// </exception>
/// <exception cref="Win32Exception">
/// There was an error opening the stream.
/// </exception>
public FileStream Open(FileMode mode, FileAccess access, FileShare share, int bufferSize, bool useAsync)
{
if (0 >= bufferSize)
{
throw new ArgumentOutOfRangeException(/*nameof*/ (bufferSize.ToString()), bufferSize, null);
}
#if NET35
FileIOPermissionAccess permAccess = CalculateAccess(mode, access);
new FileIOPermission(permAccess, FilePath).Demand();
#endif
SafeNativeMethods.NativeFileFlags flags = useAsync ? SafeNativeMethods.NativeFileFlags.Overlapped : 0;
var handle = SafeNativeMethods.SafeCreateFile(FullPath, access.ToNative(), share, IntPtr.Zero, mode, flags, IntPtr.Zero);
if (handle.IsInvalid)
{
SafeNativeMethods.ThrowLastIOError(FullPath);
}
return(new FileStream(handle, access, bufferSize, useAsync));
}
/// <summary>
/// Opens this alternate data stream.
/// </summary>
/// <param name="mode">
/// A <see cref="FileMode"/> value that specifies whether a stream is created if one does not exist,
/// and determines whether the contents of existing streams are retained or overwritten.
/// </param>
/// <param name="access">
/// A <see cref="FileAccess"/> value that specifies the operations that can be performed on the stream.
/// </param>
/// <param name="share">
/// A <see cref="FileShare"/> value specifying the type of access other threads have to the file.
/// </param>
/// <param name="bufferSize">
/// The size of the buffer to use.
/// </param>
/// <param name="useAsync">
/// <see langword="true"/> to enable async-IO;
/// otherwise, <see langword="false"/>.
/// </param>
/// <returns>
/// A <see cref="FileStream"/> for this alternate data stream.
/// </returns>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="bufferSize"/> is less than or equal to zero.
/// </exception>
/// <exception cref="SecurityException">
/// The caller does not have the required permission.
/// </exception>
/// <exception cref="UnauthorizedAccessException">
/// The caller does not have the required permission, or the file is read-only.
/// </exception>
/// <exception cref="IOException">
/// The specified file is in use.
/// </exception>
/// <exception cref="ArgumentException">
/// The path of the stream is invalid.
/// </exception>
/// <exception cref="Win32Exception">
/// There was an error opening the stream.
/// </exception>
public FileStream Open(FileMode mode, FileAccess access, FileShare share, int bufferSize, bool useAsync)
{
if (0 >= bufferSize)
{
throw new ArgumentOutOfRangeException("bufferSize", bufferSize, null);
}
FileIOPermissionAccess permAccess = CalculateAccess(mode, access);
new FileIOPermission(permAccess, _filePath).Demand();
SafeNativeMethods.NativeFileFlags flags = useAsync ? SafeNativeMethods.NativeFileFlags.Overlapped : 0;
var handle = SafeNativeMethods.SafeCreateFile(this.FullPath, SafeNativeMethods.ToNative(access), share, IntPtr.Zero, mode, flags, IntPtr.Zero);
if (handle.IsInvalid)
{
SafeNativeMethods.ThrowLastWin32Error();
}
return(new FileStream(handle, access, bufferSize, useAsync));
}
