Class StgStream

Storage API wrapper classes provide access to storage data from .NET code.

Inheritance

System.Object

StgStream

Implements

System.IDisposable

Namespace: Syncfusion.CompoundFile.XlsIO.Native

Assembly: Syncfusion.XlsIO.Base.dll

Syntax

public class StgStream : Stream, IDisposable

Constructors

StgStream(StgStream, String)

Inherit stream storage and opens its stream in Read-only mode.

Declaration

public StgStream(StgStream storage, string streamName)

Parameters

Type	Name	Description
StgStream	storage	Storage of stream.
System.String	streamName	Stream name to open.

StgStream(StgStream, String, STGM)

Inherit stream storage and opensits streams with the user specified flags.

Declaration

public StgStream(StgStream storage, string streamName, STGM streamFlags)

Parameters

Type	Name	Description
StgStream	storage	Storage to inherit.
System.String	streamName	Stream name.
STGM	streamFlags	Stream open flags.

StgStream(StgStream, String, STGM, Boolean)

Inherit storage and open or create in it stream with spcified user name

Declaration

public StgStream(StgStream storage, string streamName, STGM streamFlags, bool bCreate)

Parameters

Type	Name	Description
StgStream	storage	Inherited storage.
System.String	streamName	Stream name.
STGM	streamFlags	Stream open / create flags.
System.Boolean	bCreate	True to create stream; otherwise open.

StgStream(StgStream, String, Boolean)

Open or create stream specified by user name.

Declaration

public StgStream(StgStream storage, string streamName, bool bCreate)

Parameters

Type	Name	Description
StgStream	storage	Inherited storage.
System.String	streamName	Stream name.
System.Boolean	bCreate	True to create stream; otherwise open.

StgStream(Stream)

Create a new instance of StgStream by defoult flag.

Declaration

public StgStream(Stream stream)

Parameters

Type	Name	Description
System.IO.Stream	stream	Base stream.

StgStream(Stream, STGM)

Create a new instance of StgStream.

Declaration

public StgStream(Stream stream, STGM flags)

Parameters

Type	Name	Description
System.IO.Stream	stream	Base stream.
STGM	flags	Flags for create stream.

StgStream(String)

Open storage in Read-only mode but do not open stream. To open special stream, use OpenStream methods.

Declaration

public StgStream(string fileName)

Parameters

Type	Name	Description
System.String	fileName	Storage file name.

StgStream(String, STGM)

Open storage/compound file.

Declaration

public StgStream(string fileName, STGM flags)

Parameters

Type	Name	Description
System.String	fileName	File name of storage.
STGM	flags	Mode which must be used for open operation.

Exceptions

Type	Condition
System.ArgumentNullException	When fileName is NULL.
System.Runtime.InteropServices.ExternalException	Couldn't open the storage

StgStream(String, STGM, String, STGM)

Open storage and one stream of it.

Declaration

public StgStream(string fileName, STGM storeFlags, string streamName, STGM streamFlags)

Parameters

Type	Name	Description
System.String	fileName	File name of storage.
STGM	storeFlags	Flags that are used for storage open.
System.String	streamName	Stream name.
STGM	streamFlags	Flags which used for stream in storage open.

StgStream(String, String)

Open storage and its stream in Read-only mode.

Declaration

public StgStream(string fileName, string streamName)

Parameters

Type	Name	Description
System.String	fileName	File name.
System.String	streamName	Stream name.

Fields

DEF_READWRITE

Open storage or stream in ReadWrite mode.

Declaration

public const STGM DEF_READWRITE

Field Value

Type
STGM

DEF_STORAGE_READONLY

Options to open storage in read-only mode. Used to open already opened file.

Declaration

public const STGM DEF_STORAGE_READONLY

Field Value

Type
STGM

DEF_STORE_READONLY

Open storage in read-only mode.

Declaration

public const STGM DEF_STORE_READONLY

Field Value

Type
STGM

DEF_STREAM_CREATE

Create a new stream in storage.

Declaration

public const STGM DEF_STREAM_CREATE

Field Value

Type
STGM

DEF_STREAM_READONLY

Open storage stream in read-only mode.

Declaration

public const STGM DEF_STREAM_READONLY

Field Value

Type
STGM

Properties

CanRead

Indicates if stream supports Read operation. Read-only.

Declaration

public override bool CanRead { get; }

Property Value

Type
System.Boolean

CanSeek

Indicates if stream supports Seek operation. Read-only.

Declaration

public override bool CanSeek { get; }

Property Value

Type
System.Boolean

CanWrite

Indicates if stream supports Write operation. Read-only.

Declaration

public override bool CanWrite { get; }

Property Value

Type
System.Boolean

COMStorage

Reference in COM interface which provide access to storage.

Declaration

public IStorage COMStorage { get; }

Property Value

Type
IStorage

COMStream

Reference in COM interface which provide access to stream in storage.

Declaration

public IStream COMStream { get; }

Property Value

Type
IStream

FileName

Gets the file name.

Declaration

public string FileName { get; }

Property Value

Type
System.String

IsTransacted

Indicates if stream is opened in Transaction mode. Read-only.

Declaration

public bool IsTransacted { get; }

Property Value

Type
System.Boolean

Length

Length of stream. Read-only.

Declaration

public override long Length { get; }

Property Value

Type
System.Int64

LockBytes

Gets the IlockBytes interface that represen the locked bytes.

Declaration

public ILockBytes LockBytes { get; }

Property Value

Type
ILockBytes

Position

Gets / sets current position of stream.

Declaration

public override long Position { get; set; }

Property Value

Type
System.Int64

StorageName

Get name of sub storage opened by the class.

Declaration

public string StorageName { get; }

Property Value

Type
System.String

Storages

Gets the array of string thet is a storages.

Declaration

public string[] Storages { get; }

Property Value

Type
System.String[]

StreamName

Get name of stream opened by the class.

Declaration

public string StreamName { get; }

Property Value

Type
System.String

Streams

Gets list of stream names found in storage. Read-only.

Declaration

public string[] Streams { get; }

Property Value

Type
System.String[]

Methods

Close()

Closes the stream.

Declaration

public override void Close()

Commit(STGC)

Commit changes.

Declaration

public virtual void Commit(STGC code)

Parameters

Type	Name	Description
STGC	code	Commit code.

Exceptions

Type	Condition
System.Runtime.InteropServices.ExternalException	When commit operation fails.

ContainsStorage(String)

Indicates whether storage contains required substorage.

Declaration

public bool ContainsStorage(string strStorageName)

Parameters

Type	Name	Description
System.String	strStorageName	Storage to search.

Returns

Type	Description
System.Boolean	True if stream was found.

ContainsStream(String)

Indicates whether storage contains required stream.

Declaration

public bool ContainsStream(string strStreamName)

Parameters

Type	Name	Description
System.String	strStreamName	Stream to search.

Returns

Type	Description
System.Boolean	True if stream was found.

CopySourceStorages(StgStream, StgStream)

Copies one storage into another.

Declaration

public static void CopySourceStorages(StgStream source, StgStream destination)

Parameters

Type	Name	Description
StgStream	source	Source stream.
StgStream	destination	Destination stream.

CreateStorage(String)

Method to create new storage and return StgStream class for it.

Declaration

public static StgStream CreateStorage(string fileName)

Parameters

Type	Name	Description
System.String	fileName	Storage file name.

Returns

Type	Description
StgStream	Reference on instance which knows how to work with it.

Exceptions

Type	Condition
System.Runtime.InteropServices.ExternalException	When compound file couldn't be created.

CreateStorageOnILockBytes()

Cretes storage on ILockBytes.

Declaration

public static StgStream CreateStorageOnILockBytes()

Returns

Type	Description
StgStream	Created storage.

CreateStream(String)

Create stream in opened storage with specified name.

Declaration

public void CreateStream(string streamName)

Parameters

Type	Name	Description
System.String	streamName	Stream name.

CreateStream(String, STGM)

Create stream in storage with specified name and flags.

Declaration

public void CreateStream(string streamName, STGM streamFlags)

Parameters

Type	Name	Description
System.String	streamName	Stream name.
STGM	streamFlags	Stream flags.

Exceptions

Type	Condition
System.Runtime.InteropServices.ExternalException	When its not possible to create stream.

CreateSubStorage(String)

Creates sub storage.

Declaration

public StgStream CreateSubStorage(string storageName)

Parameters

Type	Name	Description
System.String	storageName	Storage name to Create.

Returns

Type	Description
StgStream	Returns stream of opened storage.

CreateSubStorage(String, STGM)

Creates sub storage.

Declaration

public StgStream CreateSubStorage(string storageName, STGM flags)

Parameters

Type	Name	Description
System.String	storageName	Storage name for create.
STGM	flags	Create flags.

Returns

Type	Description
StgStream	Returns stream for created storage.

Dispose()

Dispose stream. Close stream, release references on COM interfaces, and free resources.

Declaration

public void Dispose()

FindStream(String)

Searches for stream name in the streams array ignoring case.

Declaration

public string FindStream(string strStreamName)

Parameters

Type	Name	Description
System.String	strStreamName	Stream name to locate.

Returns

Type	Description
System.String	Name of the stream in the storage.

Flush()

Commit changes.

Declaration

public override void Flush()

OpenStream(String)

Open stream in Read-only mode.

Declaration

public void OpenStream(string streamName)

Parameters

Type	Name	Description
System.String	streamName	Stream name.

OpenStream(String, STGM)

Open stream from storage with specified flags.

Declaration

public void OpenStream(string streamName, STGM streamFlags)

Parameters

Type	Name	Description
System.String	streamName	Stream name.
STGM	streamFlags	Stream open flags.

Exceptions

Type	Condition
System.ArgumentNullException	When streamName is NULL.
System.ArgumentException	When the specified stream could not be found in the storage.
System.Runtime.InteropServices.ExternalException	When it was not possible to open the stream.

OpenSubStorage(String)

Opens sub storage.

Declaration

public StgStream OpenSubStorage(string storageName)

Parameters

Type	Name	Description
System.String	storageName	Storage name to open.

Returns

Type	Description
StgStream	Returns stream of opened storage.

OpenSubStorage(String, STGM)

Opens sub storage.

Declaration

public StgStream OpenSubStorage(string storageName, STGM flags)

Parameters

Type	Name	Description
System.String	storageName	Storage name to open.
STGM	flags	Open flags.

Returns

Type	Description
StgStream	Returns stream of opened storage.

Read(Byte[], Int32, Int32)

Read data from stream.

Declaration

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

Parameters

Type	Name	Description
System.Byte[]	buffer	Output stream.
System.Int32	offset	Offset in output buffer.
System.Int32	count	Quantity of bytes to read.

Returns

Type	Description
System.Int32	Quantity of read bytes.

Exceptions

Type	Condition
System.ArgumentNullException	When buffer is NULL.
System.ArgumentOutOfRangeException	When offset or count is less than zero.
System.ArgumentException	When there are not enough items in the buffer.
System.Runtime.InteropServices.ExternalException	When Read operation fails.

RemoveElement(String)

Removes the specified storage or stream from this storage object.

Declaration

public int RemoveElement(string elementName)

Parameters

Type	Name	Description
System.String	elementName	Name of the storage or stream to be removed.

Returns

Type	Description
System.Int32	0 - The element was successfully removed. Otherwise error code.

Revert()

Discards all changes that have been made to the storage object since the last commit operation.

Declaration

public virtual void Revert()

SaveILockBytesIntoStream(Stream)

Saves internal ILockBytes into stream.

Declaration

public void SaveILockBytesIntoStream(Stream stream)

Parameters

Type	Name	Description
System.IO.Stream	stream	Stream to save into.

Seek(Int64, SeekOrigin)

Seek in stream.

Declaration

public override long Seek(long offset, SeekOrigin origin)

Parameters

Type	Name	Description
System.Int64	offset	New offset.
System.IO.SeekOrigin	origin	Start point for Seek operation.

Returns

Type	Description
System.Int64	Current position.

Exceptions

Type	Condition
System.Runtime.InteropServices.ExternalException	When seek operation fails.

SetLength(Int64)

Set stream length.

Declaration

public override void SetLength(long value)

Parameters

Type	Name	Description
System.Int64	value	New stream length

Exceptions

Type	Condition
System.Runtime.InteropServices.ExternalException	When SetLength operation fails.

Write(Byte[], Int32, Int32)

Write data to stream.

Declaration

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

Parameters

Type	Name	Description
System.Byte[]	buffer	Buffer with data.
System.Int32	offset	Offset in input buffer from which data started.
System.Int32	count	Quantity of bytes which must be written.

Exceptions

Type	Condition
System.ArgumentNullException	When buffer is NULL.
System.ArgumentOutOfRangeException	When offset or count is less than zero.
System.ArgumentException	When there are not enough items in the buffer or stream is in Read-only mode.
System.Runtime.InteropServices.ExternalException	When Write operation fails.

Implements

System.IDisposable