Click here to Skip to main content
Click here to Skip to main content
Add your own
alternative version

Using AvalonEdit (WPF Text Editor)

, 1 Apr 2013
AvalonEdit is an extensible Open-Source text editor with support for syntax highlighting and folding.
AvalonEdit_4.3.1_Binaries-noexe.zip
AvalonEdit_4.3.1_Binaries.zip
AvalonEdit_4.3.1_Source-noexe.zip
AvalonEdit.Sample
AvalonEdit
dependencies.png
folding.png
renderingPipeline.png
screenshot.png
snoop.png
CustomHighlighting.xshd
Images
Copy.png
Cut.png
Delete.png
Open.png
Paste.png
Redo.png
Save.png
Undo.png
WordWrap.png
Properties
RenderingPipeline.pptx
Documentation
Architecture.aml
Code Completion.aml
Coordinate Systems.aml
Folding.aml
ICSharpCode.AvalonEdit.content
ICSharpCode.AvalonEdit.shfbproj
Media
NamespaceDependencies.png
RenderingPipeline.png
VisualTree.png
WelcomeScreenshot.png
Sample Application.aml
Syntax Highlighting.aml
Text Rendering.aml
Welcome.aml
ICSharpCode.AvalonEdit.Tests
Document
Editing
Highlighting
ICSharpCode.AvalonEdit.Tests.PartCover.Settings
Properties
Search
Utils
ICSharpCode.AvalonEdit
CodeCompletion
Document
Editing
Folding
Highlighting
Resources
ASPX.xshd
Boo.xshd
Coco-Mode.xshd
CPP-Mode.xshd
CSharp-Mode.xshd
CSS-Mode.xshd
HTML-Mode.xshd
Java-Mode.xshd
JavaScript-Mode.xshd
MarkDown-Mode.xshd
Patch-Mode.xshd
PHP-Mode.xshd
PowerShell.xshd
Tex-Mode.xshd
VBNET-Mode.xshd
XML-Mode.xshd
XmlDoc.xshd
Xshd
ICSharpCode.AvalonEdit.snk
Indentation
CSharp
Properties
Rendering
Search
next.png
prev.png
Snippets
themes
RightArrow.cur
Utils
Xml
AvalonEdit_4.3.1_Source.zip
dependencies.png
folding.png
renderingPipeline.png
screenshot.png
snoop.png
CustomHighlighting.xshd
Copy.png
Cut.png
Delete.png
Open.png
Paste.png
Redo.png
Save.png
Undo.png
WordWrap.png
RenderingPipeline.pptx
Architecture.aml
Code Completion.aml
Coordinate Systems.aml
Folding.aml
ICSharpCode.AvalonEdit.content
ICSharpCode.AvalonEdit.shfbproj
NamespaceDependencies.png
RenderingPipeline.png
VisualTree.png
WelcomeScreenshot.png
Sample Application.aml
Syntax Highlighting.aml
Text Rendering.aml
Welcome.aml
ICSharpCode.AvalonEdit.Tests.PartCover.Settings
nunit.framework.dll
ASPX.xshd
Boo.xshd
Coco-Mode.xshd
CPP-Mode.xshd
CSharp-Mode.xshd
CSS-Mode.xshd
HTML-Mode.xshd
Java-Mode.xshd
JavaScript-Mode.xshd
MarkDown-Mode.xshd
Patch-Mode.xshd
PHP-Mode.xshd
PowerShell.xshd
Tex-Mode.xshd
VBNET-Mode.xshd
XML-Mode.xshd
XmlDoc.xshd
ICSharpCode.AvalonEdit.snk
next.png
prev.png
RightArrow.cur
AvalonEdit_Binaries-noexe.zip
AvalonEdit_Binaries.zip
AvalonEdit_CHM_Documentation.zip
AvalonEdit_Source.zip
dependencies.png
folding.png
renderingPipeline.png
screenshot.png
snoop.png
CustomHighlighting.xshd
Copy.png
Cut.png
Delete.png
Open.png
Paste.png
Redo.png
Save.png
Undo.png
WordWrap.png
RenderingPipeline.pptx
Architecture.aml
Code Completion.aml
Coordinate Systems.aml
Folding.aml
Help
ICSharpCode.AvalonEdit.content
ICSharpCode.AvalonEdit.shfbproj
NamespaceDependencies.png
RenderingPipeline.png
VisualTree.png
WelcomeScreenshot.png
Sample Application.aml
Syntax Highlighting.aml
Text Rendering.aml
Welcome.aml
ICSharpCode.AvalonEdit.Tests.PartCover.Settings
nunit.framework.dll
ASPX.xshd
Boo.xshd
Coco-Mode.xshd
CPP-Mode.xshd
CSharp-Mode.xshd
CSS-Mode.xshd
HTML-Mode.xshd
Java-Mode.xshd
JavaScript-Mode.xshd
Patch-Mode.xshd
PHP-Mode.xshd
PowerShell.xshd
Tex-Mode.xshd
VBNET-Mode.xshd
XML-Mode.xshd
XmlDoc.xshd
ICSharpCode.AvalonEdit.snk
next.png
prev.png
RightArrow.cur
// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)

using ICSharpCode.AvalonEdit.Utils;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;

namespace ICSharpCode.AvalonEdit.Document
{
	/// <summary>
	/// <para>A checkpoint that allows tracking changes to a TextDocument.</para>
	/// <para>
	/// Use <see cref="TextDocument.CreateSnapshot(out ChangeTrackingCheckpoint)"/> to create a checkpoint.
	/// </para>
	/// </summary>
	/// <remarks>
	/// <para>The <see cref="ChangeTrackingCheckpoint"/> class allows tracking document changes, even from background threads.</para>
	/// <para>Once you have two checkpoints, you can call <see cref="ChangeTrackingCheckpoint.GetChangesTo"/> to retrieve the complete list
	/// of document changes that happened between those versions of the document.</para>
	/// </remarks>
	public sealed class ChangeTrackingCheckpoint
	{
		// Object that is unique per document.
		// Used to determine if two checkpoints belong to the same document.
		// We don't use a reference to the document itself to allow the GC to reclaim the document memory
		// even if there are still references to checkpoints.
		readonly object documentIdentifier;
		
		// 'value' is the change from the previous checkpoint to this checkpoint
		// TODO: store the change in the older checkpoint instead - if only a reference to the
		// newest document version exists, the GC should be able to collect all DocumentChangeEventArgs.
		readonly DocumentChangeEventArgs value;
		readonly int id;
		ChangeTrackingCheckpoint next;
		
		internal ChangeTrackingCheckpoint(object documentIdentifier)
		{
			this.documentIdentifier = documentIdentifier;
		}
		
		internal ChangeTrackingCheckpoint(object documentIdentifier, DocumentChangeEventArgs value, int id)
		{
			this.documentIdentifier = documentIdentifier;
			this.value = value;
			this.id = id;
		}
		
		internal ChangeTrackingCheckpoint Append(DocumentChangeEventArgs change)
		{
			Debug.Assert(this.next == null);
			this.next = new ChangeTrackingCheckpoint(this.documentIdentifier, change, unchecked( this.id + 1 ));
			return this.next;
		}
		
		/// <summary>
		/// Creates a change tracking checkpoint for the specified document.
		/// This method is thread-safe.
		/// If you need a ChangeTrackingCheckpoint that's consistent with a snapshot of the document,
		/// use <see cref="TextDocument.CreateSnapshot(out ChangeTrackingCheckpoint)"/>.
		/// </summary>
		public static ChangeTrackingCheckpoint Create(TextDocument document)
		{
			if (document == null)
				throw new ArgumentNullException("document");
			return document.CreateChangeTrackingCheckpoint();
		}
		
		/// <summary>
		/// Gets whether this checkpoint belongs to the same document as the other checkpoint.
		/// </summary>
		public bool BelongsToSameDocumentAs(ChangeTrackingCheckpoint other)
		{
			if (other == null)
				throw new ArgumentNullException("other");
			return documentIdentifier == other.documentIdentifier;
		}
		
		/// <summary>
		/// Compares the age of this checkpoint to the other checkpoint.
		/// </summary>
		/// <remarks>This method is thread-safe.</remarks>
		/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this checkpoint.</exception>
		/// <returns>-1 if this checkpoint is older than <paramref name="other"/>.
		/// 0 if <c>this</c>==<paramref name="other"/>.
		/// 1 if this checkpoint is newer than <paramref name="other"/>.</returns>
		public int CompareAge(ChangeTrackingCheckpoint other)
		{
			if (other == null)
				throw new ArgumentNullException("other");
			if (other.documentIdentifier != this.documentIdentifier)
				throw new ArgumentException("Checkpoints do not belong to the same document.");
			// We will allow overflows, but assume that the maximum distance between checkpoints is 2^31-1.
			// This is guaranteed on x86 because so many checkpoints don't fit into memory.
			return Math.Sign(unchecked( this.id - other.id ));
		}
		
		/// <summary>
		/// Gets the changes from this checkpoint to the other checkpoint.
		/// If 'other' is older than this checkpoint, reverse changes are calculated.
		/// </summary>
		/// <remarks>This method is thread-safe.</remarks>
		/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this checkpoint.</exception>
		public IEnumerable<DocumentChangeEventArgs> GetChangesTo(ChangeTrackingCheckpoint other)
		{
			int result = CompareAge(other);
			if (result < 0)
				return GetForwardChanges(other);
			else if (result > 0)
				return other.GetForwardChanges(this).Reverse().Select(change => change.Invert());
			else
				return Empty<DocumentChangeEventArgs>.Array;
		}
		
		IEnumerable<DocumentChangeEventArgs> GetForwardChanges(ChangeTrackingCheckpoint other)
		{
			// Return changes from this(exclusive) to other(inclusive).
			ChangeTrackingCheckpoint node = this;
			do {
				node = node.next;
				yield return node.value;
			} while (node != other);
		}
		
		/// <summary>
		/// Calculates where the offset has moved in the other buffer version.
		/// </summary>
		/// <remarks>This method is thread-safe.</remarks>
		/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this checkpoint.</exception>
		public int MoveOffsetTo(ChangeTrackingCheckpoint other, int oldOffset, AnchorMovementType movement)
		{
			int offset = oldOffset;
			foreach (DocumentChangeEventArgs e in GetChangesTo(other)) {
				offset = e.GetNewOffset(offset, movement);
			}
			return offset;
		}
	}
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The GNU Lesser General Public License (LGPLv3)

Share

About the Author

Daniel Grunwald

Germany Germany
I am the lead developer on the SharpDevelop open source project.
Follow on   Twitter   Google+   LinkedIn

| Advertise | Privacy | Mobile
Web03 | 2.8.140827.1 | Last Updated 1 Apr 2013
Article Copyright 2009 by Daniel Grunwald
Everything else Copyright © CodeProject, 1999-2014
Terms of Service
Layout: fixed | fluid