Class ChangesStream

Represents a class that provides data for the stream, that tracks changes.

Inheritance

System.Object

System.MarshalByRefObject

System.IO.Stream

ChangesStream

Implements

System.IDisposable

IChangesStream

IStream

Inherited Members

System.IO.Stream.BeginRead(System.Byte[], System.Int32, System.Int32, System.AsyncCallback, System.Object)

System.IO.Stream.BeginWrite(System.Byte[], System.Int32, System.Int32, System.AsyncCallback, System.Object)

System.IO.Stream.CanTimeout

System.IO.Stream.CopyTo(System.IO.Stream, System.Int32)

System.IO.Stream.CopyToAsync(System.IO.Stream)

System.IO.Stream.CopyToAsync(System.IO.Stream, System.Int32)

System.IO.Stream.CopyToAsync(System.IO.Stream, System.Int32, System.Threading.CancellationToken)

System.IO.Stream.CreateWaitHandle()

System.IO.Stream.Dispose(System.Boolean)

System.IO.Stream.EndRead(System.IAsyncResult)

System.IO.Stream.EndWrite(System.IAsyncResult)

System.IO.Stream.FlushAsync()

System.IO.Stream.FlushAsync(System.Threading.CancellationToken)

System.IO.Stream.Null

System.IO.Stream.ObjectInvariant()

System.IO.Stream.ReadAsync(System.Byte[], System.Int32, System.Int32)

System.IO.Stream.ReadAsync(System.Byte[], System.Int32, System.Int32, System.Threading.CancellationToken)

System.IO.Stream.ReadTimeout

System.IO.Stream.Synchronized(System.IO.Stream)

System.IO.Stream.WriteAsync(System.Byte[], System.Int32, System.Int32)

System.IO.Stream.WriteAsync(System.Byte[], System.Int32, System.Int32, System.Threading.CancellationToken)

System.IO.Stream.WriteTimeout

System.MarshalByRefObject.CreateObjRef(System.Type)

System.MarshalByRefObject.GetLifetimeService()

System.MarshalByRefObject.InitializeLifetimeService()

System.MarshalByRefObject.MemberwiseClone(System.Boolean)

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

System.Object.ToString()

Namespace: Syncfusion.Windows.Forms.Edit.Implementation.IO

Assembly: Syncfusion.Edit.Windows.dll

Syntax

public class ChangesStream : Stream, IDisposable, IChangesStream, IStream

Constructors

ChangesStream(Stream)

Initializes a new instance of the ChangesStream class.

Declaration

public ChangesStream(Stream input)

Parameters

Type	Name	Description
System.IO.Stream	input	Source stream, must support Read and Seek operations

ChangesStream(String, FileMode, FileAccess)

Initializes a new instance of the ChangesStream class.

Declaration

public ChangesStream(string FileName, FileMode mode, FileAccess access)

Parameters

Type	Name	Description
System.String	FileName	Name of the file.
System.IO.FileMode	mode	Mode of file opening.
System.IO.FileAccess	access	File access type.

Fields

DATA_WINDOW_SEARCH_COMPARER

Comparer for DataWindows.

Declaration

protected static IComparer DATA_WINDOW_SEARCH_COMPARER

Field Value

Type
System.Collections.IComparer

DEF_BUFFER_SIZE

Default buffer size.

Declaration

protected const int DEF_BUFFER_SIZE = 8192

Field Value

Type
System.Int32

DEF_FLUSH_BLOCK_LENGTH

Length of the block of data for flushing.

Declaration

protected const int DEF_FLUSH_BLOCK_LENGTH = 51200

Field Value

Type
System.Int32

Properties

AutoPush

Gets or sets the count of changes that can be done before state will be automatically pushed to stack.

Declaration

public int AutoPush { get; set; }

Property Value

Type
System.Int32

CanRead

Gets a value indicating whether the user can read data from stream.

Declaration

public override bool CanRead { get; }

Property Value

Type
System.Boolean

Overrides

System.IO.Stream.CanRead

CanRedo

Gets a value indicating whether the user can redo some actions in stream or not.

Declaration

public bool CanRedo { get; }

Property Value

Type
System.Boolean

CanSeek

Gets a value indicating whether the user can seek position in stream.

Declaration

public override bool CanSeek { get; }

Property Value

Type
System.Boolean

Overrides

System.IO.Stream.CanSeek

CanUndo

Gets a value indicating whether the user can Undo some actions in stream or not.

Declaration

public bool CanUndo { get; }

Property Value

Type
System.Boolean

CanWrite

Gets a value indicating whether the user can write the data to stream.

Declaration

public override bool CanWrite { get; }

Property Value

Type
System.Boolean

Overrides

System.IO.Stream.CanWrite

Changes

Gets list of changes.

Declaration

protected ArrayList Changes { get; }

Property Value

Type
System.Collections.ArrayList

DataWindows

Gets list of active windows.

Declaration

protected ArrayList DataWindows { get; }

Property Value

Type
System.Collections.ArrayList

LastSavedChangesCount

Looks for the last saved count of changes in the stack of Saved States

Declaration

protected int LastSavedChangesCount { get; }

Property Value

Type	Description
System.Int32	Integer value of count or -1 if stack is empty

LastSavedDataWindows

Looks for the last saved list of DataWindows in the stack of Saved States

Declaration

protected IList LastSavedDataWindows { get; }

Property Value

Type	Description
System.Collections.IList	List of data windows or null if stack is empty

Length

Gets the length of the stream

Declaration

public override long Length { get; }

Property Value

Type
System.Int64

Overrides

System.IO.Stream.Length

Position

Gets or sets the current position in the stream.

Declaration

public override long Position { get; set; }

Property Value

Type
System.Int64

Overrides

System.IO.Stream.Position

SyncObject

Gets synchronization object.

Declaration

protected object SyncObject { get; }

Property Value

Type
System.Object

Methods

AddChange(ChangeContext)

Applies change in current position.

Declaration

public void AddChange(ChangeContext context)

Parameters

Type	Name	Description
ChangeContext	context	Context of the change.

AddChange(Int64, ChangeContext)

Add change to the specified position.

Declaration

public void AddChange(long position, ChangeContext context)

Parameters

Type	Name	Description
System.Int64	position	Position in stream, where change is to be applied.
ChangeContext	context	Context of the change.

ChangeDelete(Int32, DataWindow, Int64, Int64, ref Int64, ChangeContext)

Make update of DataWindows according to Delete operation type logic

Declaration

protected void ChangeDelete(int index, DataWindow change, long start, long end, ref long posChange, ChangeContext context)

Parameters

Type	Name	Description
System.Int32	index	Index of first DataWindow in update range
DataWindow	change	DataWindow with chages
System.Int64	start	Start position of update region
System.Int64	end	End position of update region
System.Int64	posChange	influence on current stream position
ChangeContext	context	Changes to context object

ChangeInsert(Int32, DataWindow, Int64, Int64, ref Int64, DataWindow)

Make update of DataWindows according to Insert operation type logic

Declaration

protected void ChangeInsert(int index, DataWindow change, long start, long end, ref long posChange, DataWindow firstPart)

Parameters

Type	Name	Description
System.Int32	index	Index of first DataWindow in update range
DataWindow	change	DataWindow with chages
System.Int64	start	Start position of update region
System.Int64	end	End position of update region
System.Int64	posChange	influence on current stream position
DataWindow	firstPart	DataWindow to which start position belong

ChangeReplace(Int32, DataWindow, Int64, Int64, ref Int64, DataWindow, ChangeContext)

Make update of DataWindows according to Replace operation type logic

Declaration

protected void ChangeReplace(int index, DataWindow change, long start, long end, ref long posChange, DataWindow firstPart, ChangeContext context)

Parameters

Type	Name	Description
System.Int32	index	Index of first DataWindow in update range
DataWindow	change	DataWindow with chages
System.Int64	start	Start position of update region
System.Int64	end	End position of update region
System.Int64	posChange	influence on current stream position
DataWindow	firstPart	DataWindow to which start position belong
ChangeContext	context	Changes to context object

Close()

Implemented for avoiding PEVerify warnings.

Declaration

public override void Close()

Overrides

System.IO.Stream.Close()

CopyTo(Stream)

Writes current stream data to output stream.

Declaration

public void CopyTo(Stream stream)

Parameters

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

Dispose()

Frees used memory.

Declaration

public void Dispose()

ExtractLastState()

Restores datawindows and changes to the last state, saved in stack. WARNING: Method always must be called in lock( m_sync ) scope!!!

Declaration

protected void ExtractLastState()

Finalize()

Declaration

protected void Finalize()

Flush()

Saves output stream to input stream.

Declaration

public override void Flush()

Overrides

System.IO.Stream.Flush()

FlushChanges()

Saves all changes.

Declaration

public void FlushChanges()

GetDataWindowsInRange(Int64, Int64)

Searches for all data windwos in specified range.

Declaration

protected ArrayList GetDataWindowsInRange(long start, long end)

Parameters

Type	Name	Description
System.Int64	start	Start position
System.Int64	end	End position

Returns

Type	Description
System.Collections.ArrayList	Array of DataWindows which contains data from start to end points

OnPositionChanged()

Method, that is raised on every change of m_position. It means that cache must be reloaded.

Declaration

protected virtual void OnPositionChanged()

PopState()

Restores datawindows and changes to the last state, saved in stack. Last saved state is removed from stack.

Declaration

public void PopState()

PushState()

Saves current datawindows and changes to stack.

Declaration

public void PushState()

RaiseDataChangedEvent()

Raiser for DataChanged event.

Declaration

protected virtual void RaiseDataChangedEvent()

RaiseDataPositionChanged(Int64, Int64)

Raiser for DataPositionChanged event

Declaration

protected virtual void RaiseDataPositionChanged(long OldPosition, long NewPosition)

Parameters

Type	Name	Description
System.Int64	OldPosition	Old position.
System.Int64	NewPosition	New position.

RaiseRedoBufferFlushedEvent()

Raises RedoBufferFlushed event.

Declaration

protected virtual void RaiseRedoBufferFlushedEvent()

RaiseUndoBufferFlushedEvent()

Raises UndoBufferFlushed event.

Declaration

protected virtual void RaiseUndoBufferFlushedEvent()

Read(Byte[], Int32, Int32)

Reads data from stream to buffer. Reading is started from the current position.

Declaration

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

Parameters

Type	Name	Description
System.Byte[]	buffer	Array of bytes, where data must be put.
System.Int32	offset	Offset in buffer.
System.Int32	count	Count of bytes to be read.

Returns

Type	Description
System.Int32	Count of bytes, actually read.

Overrides

System.IO.Stream.Read(System.Byte[], System.Int32, System.Int32)

ReadByte()

Implemented for avoiding PEVerify warnings.

Declaration

public override int ReadByte()

Returns

Type	Description
System.Int32	Parent value.

Overrides

System.IO.Stream.ReadByte()

Redo()

Performs Redo operation to last undone change.

Declaration

public void Redo()

ResetCache()

Resets cache. Cache will be reloaded on next position change or read from stream.

Declaration

protected void ResetCache()

Seek(Int64, SeekOrigin)

Sets the current position in the stream.

Declaration

public override long Seek(long offset, SeekOrigin origin)

Parameters

Type	Name	Description
System.Int64	offset	Offset, that position must be moved for.
System.IO.SeekOrigin	origin	Specifies point, where offset must be applied.

Returns

Type	Description
System.Int64	Current position.

Overrides

System.IO.Stream.Seek(System.Int64, System.IO.SeekOrigin)

SetLength(Int64)

Sets the length of the stream.

Declaration

public override void SetLength(long value)

Parameters

Type	Name	Description
System.Int64	value	new length of stream

Overrides

System.IO.Stream.SetLength(System.Int64)

SetNewLineStyle(NewLineStyle)

Sets new line style to the underlying stream.

Declaration

public void SetNewLineStyle(NewLineStyle style)

Parameters

Type	Name	Description
NewLineStyle	style	Style of new line.

SplitDataWindow(DataWindow, Int64)

Divides one window into two in some position.

Declaration

protected DataWindow SplitDataWindow(DataWindow window, long position)

Parameters

Type	Name	Description
DataWindow	window	Window to be divided
System.Int64	position	Position in stream of division point

Returns

Type	Description
DataWindow	Second data window, that is cut

TrimDataWindows(Int32, Int64, DataWindow)

Trims datawindows in specified range.

Declaration

protected void TrimDataWindows(int index, long position, DataWindow change)

Parameters

Type	Name	Description
System.Int32	index	Index of the first datawindow, that must be cut. Can be 0, then scan of entire list will occure.
System.Int64	position	Start position of trimming.
DataWindow	change	DataWindow, which size will be used for trimming.

Undo()

Undo last change. WARNING: it simply redos all operation except the last one.

Declaration

public void Undo()

UpdateDataWindowsPositions()

Updates all window's positions. Length is also updated.

Declaration

protected void UpdateDataWindowsPositions()

UpdateDataWindowsPositions(Int32)

Updates all window's positions starting from some index. Length is also updated.

Declaration

protected void UpdateDataWindowsPositions(int start)

Parameters

Type	Name	Description
System.Int32	start	Index of the first windwo to be updated

Write(Byte[], Int32, Int32)

Writes data to stream from current position. It executes AddChange method with Insert change type.

Declaration

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

Parameters

Type	Name	Description
System.Byte[]	buffer	Data to be written.
System.Int32	offset	Offset of data to be written in buffer.
System.Int32	count	Count of bytes to be written.

Overrides

System.IO.Stream.Write(System.Byte[], System.Int32, System.Int32)

WriteByte(Byte)

Implemented for avoiding PEVerify warnings.

Declaration

public override void WriteByte(byte value)

Parameters

Type	Name	Description
System.Byte	value	Byte to write.

Overrides

System.IO.Stream.WriteByte(System.Byte)

Events

AutoPushChanged

Occurs when AutoPush property value is changed.

Declaration

public event ValueChangedEventHandler AutoPushChanged

Event Type

Type
ValueChangedEventHandler

DataChanged

Occurs after the data has changed in stream.

Declaration

public event EventHandler DataChanged

Event Type

Type
System.EventHandler

DataPositionChanged

Occurs when position of some data was changed. Example: if some data was deleted, data, that is after deleted block, will be moved back for the length of deleted data, so it`s position will be changed.

Declaration

public event ValueChangedEventHandler DataPositionChanged

Event Type

Type
ValueChangedEventHandler

RedoBufferFlushed

Occurs when redo buffer is flushed.

Declaration

public event EventHandler RedoBufferFlushed

Event Type

Type
System.EventHandler

UndoBufferFlushed

Occurs when undo buffer is flushed.

Declaration

public event EventHandler UndoBufferFlushed

Event Type

Type
System.EventHandler

Implements

System.IDisposable

IChangesStream

IStream

Extension Methods

ExtensionMethods.GetBytes(Stream)

ExtensionMethods.CopyTo(Stream, Stream)