MemoryMappedViewStream Class

Definition

Namespace:

System.IO.MemoryMappedFiles

Assembly:

System.IO.MemoryMappedFiles.dll

Source:

MemoryMappedViewStream.cs

Represents a view of a memory-mapped file as a sequentially accessed stream.

public ref class MemoryMappedViewStream sealed : System::IO::UnmanagedMemoryStream

public sealed class MemoryMappedViewStream : System.IO.UnmanagedMemoryStream

type MemoryMappedViewStream = class
    inherit UnmanagedMemoryStream

Public NotInheritable Class MemoryMappedViewStream
Inherits UnmanagedMemoryStream

Inheritance

Object

MarshalByRefObject

Stream

UnmanagedMemoryStream

MemoryMappedViewStream

Examples

The following example obtains a MemoryMappedViewStream of a memory-mapped file and writes a value to the stream for inter-process communication.

This code example is part of a larger example provided for the MemoryMappedFile.CreateNew method.

using (MemoryMappedViewStream stream = mmf.CreateViewStream())
{
    BinaryWriter writer = new BinaryWriter(stream);
    writer.Write(1);
}

Using Stream As MemoryMappedViewStream = mmf.CreateViewStream()
    Dim writer As BinaryWriter = New BinaryWriter(Stream)
    writer.Write(1)
End Using

Remarks

Use the CreateViewStream method of a MemoryMappedFile object to get this stream.

Properties

CanRead	Gets a value indicating whether a stream supports reading. (Inherited from UnmanagedMemoryStream)
CanSeek	Gets a value indicating whether a stream supports seeking. (Inherited from UnmanagedMemoryStream)
CanTimeout	Gets a value that determines whether the current stream can time out. (Inherited from Stream)
CanWrite	Gets a value indicating whether a stream supports writing. (Inherited from UnmanagedMemoryStream)
Capacity	Gets the stream length (size) or the total amount of memory assigned to a stream (capacity). (Inherited from UnmanagedMemoryStream)
Length	Gets the length of the data in a stream. (Inherited from UnmanagedMemoryStream)
PointerOffset	Gets the number of bytes by which the starting position of this view is offset from the beginning of the memory-mapped file.
Position	Gets or sets the current position in a stream. (Inherited from UnmanagedMemoryStream)
PositionPointer	Gets or sets a byte pointer to a stream based on the current position in the stream. (Inherited from UnmanagedMemoryStream)
ReadTimeout	Gets or sets a value, in milliseconds, that determines how long the stream will attempt to read before timing out. (Inherited from Stream)
SafeMemoryMappedViewHandle	Gets a handle to the view of a memory-mapped file.
WriteTimeout	Gets or sets a value, in milliseconds, that determines how long the stream will attempt to write before timing out. (Inherited from Stream)

Methods

BeginRead(Byte[], Int32, Int32, AsyncCallback, Object)	Begins an asynchronous read operation. (Consider using ReadAsync(Byte[], Int32, Int32) instead.) (Inherited from Stream)
BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object)	Begins an asynchronous write operation. (Consider using WriteAsync(Byte[], Int32, Int32) instead.) (Inherited from Stream)
Close()	Closes the current stream and releases any resources (such as sockets and file handles) associated with the current stream. Instead of calling this method, ensure that the stream is properly disposed. (Inherited from Stream)
CopyTo(Stream)	Reads the bytes from the current stream and writes them to another stream. Both streams positions are advanced by the number of bytes copied. (Inherited from Stream)
CopyTo(Stream, Int32)	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. (Inherited from Stream)
CopyToAsync(Stream)	Asynchronously reads the bytes from the current stream and writes them to another stream. Both streams positions are advanced by the number of bytes copied. (Inherited from Stream)
CopyToAsync(Stream, CancellationToken)	Asynchronously reads the bytes from the current stream and writes them to another stream, using a specified cancellation token. Both streams positions are advanced by the number of bytes copied. (Inherited from Stream)
CopyToAsync(Stream, Int32)	Asynchronously 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. (Inherited from Stream)
CopyToAsync(Stream, Int32, 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. (Inherited from Stream)
CreateObjRef(Type)	Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject)
CreateWaitHandle()	Obsolete. Allocates a WaitHandle object. (Inherited from Stream)
Dispose()	Releases all resources used by the Stream. (Inherited from Stream)
Dispose(Boolean)	Releases the unmanaged resources used by the UnmanagedMemoryStream and optionally releases the managed resources. (Inherited from UnmanagedMemoryStream)
DisposeAsync()	Asynchronously releases the unmanaged resources used by the Stream. (Inherited from Stream)
EndRead(IAsyncResult)	Waits for the pending asynchronous read to complete. (Consider using ReadAsync(Byte[], Int32, Int32) instead.) (Inherited from Stream)
EndWrite(IAsyncResult)	Ends an asynchronous write operation. (Consider using WriteAsync(Byte[], Int32, Int32) instead.) (Inherited from Stream)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
Flush()	Clears all buffers for this stream and causes any buffered data to be written to the underlying file.
FlushAsync()	Asynchronously clears all buffers for this stream and causes any buffered data to be written to the underlying device. (Inherited from Stream)
FlushAsync(CancellationToken)	Overrides the FlushAsync(CancellationToken) method so that the operation is cancelled if specified, but no other action is performed. (Inherited from UnmanagedMemoryStream)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetLifetimeService()	Obsolete. Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject)
GetType()	Gets the Type of the current instance. (Inherited from Object)
Initialize(Byte*, Int64, Int64, FileAccess)	Initializes a new instance of the UnmanagedMemoryStream class by using a pointer to an unmanaged memory location. (Inherited from UnmanagedMemoryStream)
Initialize(SafeBuffer, Int64, Int64, FileAccess)	Initializes a new instance of the UnmanagedMemoryStream class in a safe buffer with a specified offset, length, and file access. (Inherited from UnmanagedMemoryStream)
InitializeLifetimeService()	Obsolete. Obtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
MemberwiseClone(Boolean)	Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject)
ObjectInvariant()	Obsolete. Provides support for a Contract. (Inherited from Stream)
Read(Byte[], Int32, Int32)	Reads the specified number of bytes into the specified array. (Inherited from UnmanagedMemoryStream)
Read(Span<Byte>)	Reads all the bytes of this unmanaged memory stream into the specified span of bytes. (Inherited from UnmanagedMemoryStream)
ReadAsync(Byte[], Int32, Int32)	Asynchronously reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read. (Inherited from Stream)
ReadAsync(Byte[], Int32, Int32, CancellationToken)	Asynchronously reads the specified number of bytes into the specified array. (Inherited from UnmanagedMemoryStream)
ReadAsync(Memory<Byte>, CancellationToken)	Asynchronously reads the unmanaged memory stream bytes into the memory region. (Inherited from UnmanagedMemoryStream)
ReadAtLeast(Span<Byte>, Int32, Boolean)	Reads at least a minimum number of bytes from the current stream and advances the position within the stream by the number of bytes read. (Inherited from Stream)
ReadAtLeastAsync(Memory<Byte>, Int32, Boolean, CancellationToken)	Asynchronously reads at least a minimum number of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests. (Inherited from Stream)
ReadByte()	Reads a byte from a stream and advances the position within the stream by one byte, or returns -1 if at the end of the stream. (Inherited from UnmanagedMemoryStream)
ReadExactly(Byte[], Int32, Int32)	Reads count number of bytes from the current stream and advances the position within the stream. (Inherited from Stream)
ReadExactly(Span<Byte>)	Reads bytes from the current stream and advances the position within the stream until the buffer is filled. (Inherited from Stream)
ReadExactlyAsync(Byte[], Int32, Int32, CancellationToken)	Asynchronously reads count number of bytes from the current stream, advances the position within the stream, and monitors cancellation requests. (Inherited from Stream)
ReadExactlyAsync(Memory<Byte>, CancellationToken)	Asynchronously reads bytes from the current stream, advances the position within the stream until the buffer is filled, and monitors cancellation requests. (Inherited from Stream)
Seek(Int64, SeekOrigin)	Sets the current position of the current stream to the given value. (Inherited from UnmanagedMemoryStream)
SetLength(Int64)	Sets the length of the current stream.
ToString()	Returns a string that represents the current object. (Inherited from Object)
Write(Byte[], Int32, Int32)	Writes a block of bytes to the current stream using data from a buffer. (Inherited from UnmanagedMemoryStream)
Write(ReadOnlySpan<Byte>)	Writes a block of bytes to the current unmanaged memory stream using data from the provided span of bytes. (Inherited from UnmanagedMemoryStream)
WriteAsync(Byte[], Int32, Int32)	Asynchronously writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written. (Inherited from Stream)
WriteAsync(Byte[], Int32, Int32, 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. (Inherited from UnmanagedMemoryStream)
WriteAsync(ReadOnlyMemory<Byte>, CancellationToken)	Asynchronously writes a span of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests. (Inherited from UnmanagedMemoryStream)
WriteByte(Byte)	Writes a byte to the current position in the file stream. (Inherited from UnmanagedMemoryStream)

Extension Methods

CopyToAsync(Stream, PipeWriter, CancellationToken)	Asynchronously reads the bytes from the Stream and writes them to the specified PipeWriter, using a cancellation token.
ConfigureAwait(IAsyncDisposable, Boolean)	Configures how awaits on the tasks returned from an async disposable will be performed.

See also

• Memory-Mapped Files