RestrictedStream Class

Namespace: Meziantou.Framework
Assembly: Meziantou.Framework.dll
Package: Meziantou.Framework 6.0.18
Source: RestrictedStream.cs
Available in package assets: net10.0net11.0

A wrapper stream that restricts access to specific operations based on configured options.

public sealed class RestrictedStream : Stream

Inheritance: Stream RestrictedStream

Constructors

Name	Description
RestrictedStream(Stream, RestrictedStreamOptions)	A wrapper stream that restricts access to specific operations based on configured options.

RestrictedStream(Stream, RestrictedStreamOptions)

RestrictedStream.cs

A wrapper stream that restricts access to specific operations based on configured options.

public RestrictedStream(Stream stream, RestrictedStreamOptions options)

Parameters

stream Stream: The underlying stream to wrap.
options RestrictedStreamOptions: The options that control which operations are allowed.

Properties

Name	Description
CanRead	When overridden in a derived class, gets a value indicating whether the current stream supports reading.
CanSeek	When overridden in a derived class, gets a value indicating whether the current stream supports seeking.
CanWrite	When overridden in a derived class, gets a value indicating whether the current stream supports writing.
Length	When overridden in a derived class, gets the length in bytes of the stream.
Position	When overridden in a derived class, gets or sets the position within the current stream.

CanRead

RestrictedStream.cs

When overridden in a derived class, gets a value indicating whether the current stream supports reading.

public override bool CanRead { get; }

Property value

bool

CanSeek

RestrictedStream.cs

When overridden in a derived class, gets a value indicating whether the current stream supports seeking.

public override bool CanSeek { get; }

Property value

bool

CanWrite

RestrictedStream.cs

When overridden in a derived class, gets a value indicating whether the current stream supports writing.

public override bool CanWrite { get; }

Property value

bool

Length

RestrictedStream.cs

When overridden in a derived class, gets the length in bytes of the stream.

public override long Length { get; }

Property value

long

Exceptions

NotSupportedException: A class derived from Stream does not support seeking and the length is unknown.
ObjectDisposedException: Methods were called after the stream was closed.

Position

RestrictedStream.cs

When overridden in a derived class, gets or sets the position within the current stream.

public override long Position { get; set; }

Property value

long

Exceptions

IOException: An I/O error occurs.
NotSupportedException: The stream does not support seeking.
ObjectDisposedException: Methods were called after the stream was closed.

Methods

Name	Description
BeginRead(byte[], int, int, AsyncCallback?, object?)	Begins an asynchronous read operation. (Consider using `Stream.ReadAsync` instead.)
BeginWrite(byte[], int, int, AsyncCallback?, object?)	Begins an asynchronous write operation. (Consider using `Stream.WriteAsync` instead.)
CopyTo(Stream, int)	Reads the bytes from the current stream and writes them to another stream, using a specified buffer size. Both streams positions are advanced by the number of bytes copied.
CopyToAsync(Stream, int, CancellationToken)	Asynchronously reads the bytes from the current stream and writes them to another stream, using a specified buffer size and cancellation token. Both streams positions are advanced by the number of bytes copied.
DisposeAsync()	Asynchronously releases the unmanaged resources used by the `Stream`.
EndRead(IAsyncResult)	Waits for the pending asynchronous read to complete. (Consider using `Stream.ReadAsync` instead.)
EndWrite(IAsyncResult)	Ends an asynchronous write operation. (Consider using `Stream.WriteAsync` instead.)
Flush()	When overridden in a derived class, clears all buffers for this stream and causes any buffered data to be written to the underlying device.
FlushAsync(CancellationToken)	Asynchronously clears all buffers for this stream, causes any buffered data to be written to the underlying device, and monitors cancellation requests.
Read(byte[], int, int)	When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.
Read(Span<byte>)	When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.
ReadAsync(byte[], int, int, CancellationToken)	Asynchronously reads a sequence of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests.
ReadAsync(Memory<byte>, CancellationToken)	Asynchronously reads a sequence of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests.
ReadByte()	Reads a byte from the stream and advances the position within the stream by one byte, or returns -1 if at the end of the stream.
Seek(long, SeekOrigin)	When overridden in a derived class, sets the position within the current stream.
SetLength(long)	When overridden in a derived class, sets the length of the current stream.
Write(byte[], int, int)	When overridden in a derived class, writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.
Write(ReadOnlySpan<byte>)	When overridden in a derived class, writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.
WriteAsync(byte[], int, int, CancellationToken)	Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.
WriteAsync(ReadOnlyMemory<byte>, CancellationToken)	Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.
WriteByte(byte)	Writes a byte to the current position in the stream and advances the position within the stream by one byte.

BeginRead(byte[], int, int, AsyncCallback?, object?)

RestrictedStream.cs

Begins an asynchronous read operation. (Consider using Stream.ReadAsync instead.)

public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback? callback, object? state)

Parameters

buffer byte[]: The buffer to read the data into.
offset int: The byte offset in buffer at which to begin writing data read from the stream.
count int: The maximum number of bytes to read.
callback AsyncCallback?: An optional asynchronous callback, to be called when the read is complete.
state object?: A user-provided object that distinguishes this particular asynchronous read request from other requests.

Returns

IAsyncResult An IAsyncResult that represents the asynchronous read, which could still be pending.

Exceptions

IOException: Attempted an asynchronous read past the end of the stream, or a disk error occurs.
ArgumentException: One or more of the arguments is invalid.
ObjectDisposedException: Methods were called after the stream was closed.
NotSupportedException: The current Stream implementation does not support the read operation.

BeginWrite(byte[], int, int, AsyncCallback?, object?)

RestrictedStream.cs

Begins an asynchronous write operation. (Consider using Stream.WriteAsync instead.)

public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback? callback, object? state)

Parameters

buffer byte[]: The buffer to write data from.
offset int: The byte offset in buffer from which to begin writing.
count int: The maximum number of bytes to write.
callback AsyncCallback?: An optional asynchronous callback, to be called when the write is complete.
state object?: A user-provided object that distinguishes this particular asynchronous write request from other requests.

Returns

IAsyncResult An IAsyncResult that represents the asynchronous write, which could still be pending.

Exceptions

IOException: Attempted an asynchronous write past the end of the stream, or a disk error occurs.
ArgumentException: One or more of the arguments is invalid.
ObjectDisposedException: Methods were called after the stream was closed.
NotSupportedException: The current Stream implementation does not support the write operation.

CopyTo(Stream, int)

RestrictedStream.cs

Reads the bytes from the current stream and writes them to another stream, using a specified buffer size. Both streams positions are advanced by the number of bytes copied.

public override void CopyTo(Stream destination, int bufferSize)

Parameters

destination Stream: The stream to which the contents of the current stream will be copied.
bufferSize int: The size of the buffer. This value must be greater than zero. The default size is 81920.

Exceptions

ArgumentNullException: destination is null.
ArgumentOutOfRangeException: bufferSize is negative or zero.
NotSupportedException: The current stream does not support reading. -or- destination does not support writing.
ObjectDisposedException: Either the current stream or destination were closed before the Stream.CopyTo method was called.
IOException: An I/O error occurred.

CopyToAsync(Stream, int, CancellationToken)

RestrictedStream.cs

Asynchronously reads the bytes from the current stream and writes them to another stream, using a specified buffer size and cancellation token. Both streams positions are advanced by the number of bytes copied.

public override Task CopyToAsync(Stream destination, int bufferSize, CancellationToken cancellationToken)

Parameters

destination Stream: The stream to which the contents of the current stream will be copied.
bufferSize int: The size, in bytes, of the buffer. This value must be greater than zero. The default size is 81920.
cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

Task A task that represents the asynchronous copy operation.

Exceptions

ArgumentNullException: destination is null.
ArgumentOutOfRangeException: bufferSize is negative or zero.
ObjectDisposedException: Either the current stream or the destination stream is disposed.
NotSupportedException: The current stream does not support reading, or the destination stream does not support writing.
OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

DisposeAsync()

RestrictedStream.cs

Asynchronously releases the unmanaged resources used by the Stream.

net10.0

public override ValueTask DisposeAsync()

net11.0

public override ValueTask DisposeAsync()

Returns

ValueTask A task that represents the asynchronous dispose operation.

EndRead(IAsyncResult)

RestrictedStream.cs

Waits for the pending asynchronous read to complete. (Consider using Stream.ReadAsync instead.)

public override int EndRead(IAsyncResult asyncResult)

Parameters

asyncResult IAsyncResult: The reference to the pending asynchronous request to finish.

Returns

int The number of bytes read from the stream, between zero (0) and the number of bytes requested. ReadAsync returns zero (0) only if zero bytes were requested or if no more bytes will be available because it's at the end of the stream; otherwise, read operations do not complete until at least one byte is available. If zero bytes are requested, read operations may complete immediately or may not complete until at least one byte is available (but without consuming any data).

Exceptions

ArgumentNullException: asyncResult is null.
ArgumentException: A handle to the pending read operation is not available. -or- The pending operation does not support reading.
InvalidOperationException: asyncResult did not originate from a Stream.BeginRead method on the current stream.
IOException: The stream is closed or an internal error has occurred.

EndWrite(IAsyncResult)

RestrictedStream.cs

Ends an asynchronous write operation. (Consider using Stream.WriteAsync instead.)

public override void EndWrite(IAsyncResult asyncResult)

Parameters

asyncResult IAsyncResult: A reference to the outstanding asynchronous I/O request.

Exceptions

ArgumentNullException: asyncResult is null.
ArgumentException: A handle to the pending write operation is not available. -or- The pending operation does not support writing.
InvalidOperationException: asyncResult did not originate from a Stream.BeginWrite method on the current stream.
IOException: The stream is closed or an internal error has occurred.

Flush()

RestrictedStream.cs

When overridden in a derived class, clears all buffers for this stream and causes any buffered data to be written to the underlying device.

public override void Flush()

Exceptions

IOException: An I/O error occurs.

FlushAsync(CancellationToken)

RestrictedStream.cs

Asynchronously clears all buffers for this stream, causes any buffered data to be written to the underlying device, and monitors cancellation requests.

public override Task FlushAsync(CancellationToken cancellationToken)

Parameters

cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

Task A task that represents the asynchronous flush operation.

Exceptions

ObjectDisposedException: The stream has been disposed.
OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

Read overloads

Read(byte[], int, int)

RestrictedStream.cs

When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.

public override int Read(byte[] buffer, int offset, int count)

Parameters

buffer byte[]: An array of bytes. When this method returns, the buffer contains the specified byte array with the values between offset and (offset + count - 1) replaced by the bytes read from the current source.
offset int: The zero-based byte offset in buffer at which to begin storing the data read from the current stream.
count int: The maximum number of bytes to be read from the current stream.

Returns

int The total number of bytes read into the buffer. This can be less than the number of bytes requested if that many bytes are not currently available, or zero (0) if count is 0 or the end of the stream has been reached.

Exceptions

ArgumentException: The sum of offset and count is larger than the buffer length.
ArgumentNullException: buffer is null.
ArgumentOutOfRangeException: offset or count is negative.
IOException: An I/O error occurs.
NotSupportedException: The stream does not support reading.
ObjectDisposedException: Methods were called after the stream was closed.

Read(Span<byte>)

RestrictedStream.cs

When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.

public override int Read(Span<byte> buffer)

Parameters

buffer Span<byte>: A region of memory. When this method returns, the contents of this region are replaced by the bytes read from the current source.

Returns

int The total number of bytes read into the buffer. This can be less than the size of the buffer if that many bytes are not currently available, or zero (0) if the buffer's length is zero or the end of the stream has been reached.

ReadAsync overloads

ReadAsync(byte[], int, int, CancellationToken)

RestrictedStream.cs

Asynchronously reads a sequence of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests.

public override Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)

Parameters

buffer byte[]: The buffer to write the data into.
offset int: The byte offset in buffer at which to begin writing data from the stream.
count int: The maximum number of bytes to read.
cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

Task<int> A task that represents the asynchronous read operation. The value of the TResult parameter contains the total number of bytes read into the buffer. The result value can be less than the number of bytes requested if the number of bytes currently available is less than the requested number, or it can be 0 (zero) if count is 0 or if the end of the stream has been reached.

Exceptions

ArgumentNullException: buffer is null.
ArgumentOutOfRangeException: offset or count is negative.
ArgumentException: The sum of offset and count is larger than the buffer length.
NotSupportedException: The stream does not support reading.
ObjectDisposedException: The stream has been disposed.
InvalidOperationException: The stream is currently in use by a previous read operation.
OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

ReadAsync(Memory<byte>, CancellationToken)

RestrictedStream.cs

Asynchronously reads a sequence of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests.

public override ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken cancellationToken = default)

Parameters

buffer Memory<byte>: The region of memory to write the data into.
cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

ValueTask<int> A task that represents the asynchronous read operation. The value of its ValueTask<TResult>.Result property contains the total number of bytes read into the buffer. The result value can be less than the length of the buffer if that many bytes are not currently available, or it can be 0 (zero) if the length of the buffer is 0 or if the end of the stream has been reached.

Exceptions

OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

ReadByte()

RestrictedStream.cs

Reads a byte from the stream and advances the position within the stream by one byte, or returns -1 if at the end of the stream.

public override int ReadByte()

Returns

int The unsigned byte cast to an Int32, or -1 if at the end of the stream.

Exceptions

NotSupportedException: The stream does not support reading.
ObjectDisposedException: Methods were called after the stream was closed.

Seek(long, SeekOrigin)

RestrictedStream.cs

When overridden in a derived class, sets the position within the current stream.

public override long Seek(long offset, SeekOrigin origin)

Parameters

offset long: A byte offset relative to the origin parameter.
origin SeekOrigin: A value of type SeekOrigin indicating the reference point used to obtain the new position.

Returns

long The new position within the current stream.

Exceptions

IOException: An I/O error occurs.
NotSupportedException: The stream does not support seeking, such as if the stream is constructed from a pipe or console output.
ObjectDisposedException: Methods were called after the stream was closed.

SetLength(long)

RestrictedStream.cs

When overridden in a derived class, sets the length of the current stream.

public override void SetLength(long value)

Parameters

value long: The desired length of the current stream in bytes.

Exceptions

IOException: An I/O error occurs.
NotSupportedException: The stream does not support both writing and seeking, such as if the stream is constructed from a pipe or console output.
ObjectDisposedException: Methods were called after the stream was closed.

Write overloads

Write(byte[], int, int)

RestrictedStream.cs

When overridden in a derived class, writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.

public override void Write(byte[] buffer, int offset, int count)

Parameters

buffer byte[]: An array of bytes. This method copies count bytes from buffer to the current stream.
offset int: The zero-based byte offset in buffer at which to begin copying bytes to the current stream.
count int: The number of bytes to be written to the current stream.

Exceptions

ArgumentException: The sum of offset and count is greater than the buffer length.
ArgumentNullException: buffer is null.
ArgumentOutOfRangeException: offset or count is negative.
IOException: An I/O error occurred, such as the specified file cannot be found.
NotSupportedException: The stream does not support writing.
ObjectDisposedException: Stream.Write was called after the stream was closed.

Write(ReadOnlySpan<byte>)

RestrictedStream.cs

When overridden in a derived class, writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.

public override void Write(ReadOnlySpan<byte> buffer)

Parameters

buffer ReadOnlySpan<byte>: A region of memory. This method copies the contents of this region to the current stream.

WriteAsync overloads

WriteAsync(byte[], int, int, CancellationToken)

RestrictedStream.cs

Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.

public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)

Parameters

buffer byte[]: The buffer to write data from.
offset int: The zero-based byte offset in buffer from which to begin copying bytes to the stream.
count int: The maximum number of bytes to write.
cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

Task A task that represents the asynchronous write operation.

Exceptions

ArgumentNullException: buffer is null.
ArgumentOutOfRangeException: offset or count is negative.
ArgumentException: The sum of offset and count is larger than the buffer length.
NotSupportedException: The stream does not support writing.
ObjectDisposedException: The stream has been disposed.
InvalidOperationException: The stream is currently in use by a previous write operation.
OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

WriteAsync(ReadOnlyMemory<byte>, CancellationToken)

RestrictedStream.cs

Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.

public override ValueTask WriteAsync(ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken = default)

Parameters

buffer ReadOnlyMemory<byte>: The region of memory to write data from.
cancellationToken CancellationToken: The token to monitor for cancellation requests. The default value is CancellationToken.None.

Returns

ValueTask A task that represents the asynchronous write operation.

Exceptions

OperationCanceledException: The cancellation token was canceled. This exception is stored into the returned task.

WriteByte(byte)

RestrictedStream.cs

Writes a byte to the current position in the stream and advances the position within the stream by one byte.

public override void WriteByte(byte value)

Parameters

value byte: The byte to write to the stream.

Exceptions

IOException: An I/O error occurs.
NotSupportedException: The stream does not support writing, or the stream is already closed.
ObjectDisposedException: Methods were called after the stream was closed.