SqlFileStream Class
Definition
Important
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Exposes SQL Server data that is stored with the FILESTREAM column attribute as a sequence of bytes.
public ref class SqlFileStream sealed : System::IO::Streampublic sealed class SqlFileStream : System.IO.Streamtype SqlFileStream = class
inherit StreamPublic NotInheritable Class SqlFileStream
Inherits Stream- Inheritance
Remarks
The SqlFileStream class is used to work with varbinary(max) data stored with the FILESTREAM attribute in a SQL Server 2008 database. You must install the .NET Framework 3.5 SP1 (or later) to use SqlFileStream to work with FILESTREAM data.
Specifying the FILESTREAM attribute on a varbinary(max) column causes SQL Server to store the data in the local NTFS file system instead of in the database file. Transact-SQL statements provide data manipulation capabilities within the server, and Win32 file system interfaces provide streaming access to the data.
Note
Individual files stored in a FILESTREAM column cannot be opened directly from the NTFS file system. Streaming FILESTREAM data works only in the context of a SQL Server transaction.
The SqlFileStream class is derived from the Stream class, which represents an abstraction of a sequence of bytes from some arbitrary data source such as a file or a block of memory. You can read from a FILESTREAM by transferring data from a stream into a data structure such as an array of bytes. You can write to a FILESTREAM by transferring the data from a data structure into a stream. You can also seek within the stream, which allows you to query and modify data at the current position within the stream.
For conceptual documentation and code examples, see FILESTREAM Data.
For documentation about setting up and configuring FILESTREAM data on SQL Server, see Designing and Implementing FILESTREAM Storage in SQL Server 2008 Books Online.
Constructors
| SqlFileStream(String, Byte[], FileAccess) |
Initializes a new instance of the SqlFileStream class. |
| SqlFileStream(String, Byte[], FileAccess, FileOptions, Int64) |
Initializes a new instance of the SqlFileStream class. |
Properties
| CanRead |
Gets a value indicating whether the current stream supports reading. |
| CanSeek |
Gets a value indicating whether the current stream supports seeking. |
| CanTimeout |
Gets a value indicating whether the current stream can time out. |
| CanWrite |
Gets a value indicating whether the current stream supports writing. |
| Length |
Gets a value indicating the length of the current stream in bytes. |
| Name |
Gets the logical path of the SqlFileStream passed to the constructor. |
| Position |
Gets or sets the position within the current stream. |
| ReadTimeout |
Gets or sets a value, in milliseconds, that determines how long the stream will attempt to read before timing out. |
| TransactionContext |
Gets or sets the transaction context for this SqlFileStream object. |
| WriteTimeout |
Gets or sets a value, in milliseconds, that determines how long the stream will attempt to write before timing out. |
Methods
| BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) |
Begins an asynchronous read operation. |
| BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object) |
Begins an asynchronous write operation. |
| 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.
Obsolete.
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 Stream and optionally releases the managed resources. (Inherited from Stream) |
| DisposeAsync() |
Asynchronously releases the unmanaged resources used by the Stream. (Inherited from Stream) |
| EndRead(IAsyncResult) |
Waits for the pending asynchronous read to complete. |
| EndWrite(IAsyncResult) |
Ends an asynchronous write operation. |
| Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
| Finalize() |
Ensures that resources are freed and other cleanup operations are performed when the garbage collector reclaims the SqlFileStream. |
| Flush() |
clears all buffers for this stream and causes any buffered data to be written to the underlying device. |
| 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) |
Asynchronously clears all buffers for this stream, causes any buffered data to be written to the underlying device, and monitors cancellation requests. (Inherited from Stream) |
| 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) |
| 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 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. (Inherited from Stream) |
| 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 a sequence 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) |
| 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. (Inherited from Stream) |
| 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 the stream and advances the position within the stream by one byte, or returns -1 if at the end of the stream. |
| ReadExactly(Byte[], Int32, Int32) |
Reads |
| ReadExactly(Span<Byte>) |
Reads bytes from the current stream and advances the position within the stream until the |
| ReadExactlyAsync(Byte[], Int32, Int32, CancellationToken) |
Asynchronously reads |
| ReadExactlyAsync(Memory<Byte>, CancellationToken) |
Asynchronously reads bytes from the current stream, advances the position within the stream until the |
| Seek(Int64, SeekOrigin) |
Sets the position within the current stream. |
| 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 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. (Inherited from Stream) |
| 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 Stream) |
| 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. (Inherited from Stream) |
| WriteByte(Byte) |
Writes a byte to the current position in the stream and advances the position within the stream by one byte. |
Extension Methods
| CopyToAsync(Stream, PipeWriter, CancellationToken) |
Asynchronously reads the bytes from the Stream and writes them to the specified PipeWriter, using a cancellation token. |
