DocumentFormat.OpenXml 3.0.0-beta0002

.NET 6.0 This package targets .NET 6.0. The package is compatible with this framework or higher. .NET Standard 2.0 This package targets .NET Standard 2.0. The package is compatible with this framework or higher. .NET Framework 3.5 This package targets .NET Framework 3.5. The package is compatible with this framework or higher.
This is a prerelease version of DocumentFormat.OpenXml.
There is a newer version of this package available.
See the version list below for details. 
dotnet add package DocumentFormat.OpenXml --version 3.0.0-beta0002                

                    
                

            
NuGet\Install-Package DocumentFormat.OpenXml -Version 3.0.0-beta0002
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package. 
<PackageReference Include="DocumentFormat.OpenXml" Version="3.0.0-beta0002" />
For projects that support PackageReference, copy this XML node into the project file to reference the package. 
paket add DocumentFormat.OpenXml --version 3.0.0-beta0002                

                    
                

            
#r "nuget: DocumentFormat.OpenXml, 3.0.0-beta0002"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package. 
// Install DocumentFormat.OpenXml as a Cake Addin
#addin nuget:?package=DocumentFormat.OpenXml&version=3.0.0-beta0002&prerelease

// Install DocumentFormat.OpenXml as a Cake Tool
#tool nuget:?package=DocumentFormat.OpenXml&version=3.0.0-beta0002&prerelease

The Open XML SDK provides tools for working with Office Word, Excel, and PowerPoint documents. It supports scenarios such as:

- High-performance generation of word-processing documents, spreadsheets, and presentations.
- Populating content in Word files from an XML data source.
- Splitting up (shredding) a Word or PowerPoint file into multiple files, and combining multiple Word/PowerPoint files into a single file.
- Extraction of data from Excel documents.
- Searching and replacing content in Word/PowerPoint using regular expressions.
- Updating cached data and embedded spreadsheets for charts in Word/PowerPoint.
- Document modification, such as removing tracked revisions or removing unacceptable content from documents.

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 is compatible.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed. 
.NET Core netcoreapp2.0 was computed.  netcoreapp2.1 was computed.  netcoreapp2.2 was computed.  netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.0 is compatible.  netstandard2.1 was computed. 
.NET Framework net35 is compatible.  net40 is compatible.  net403 was computed.  net45 was computed.  net451 was computed.  net452 was computed.  net46 is compatible.  net461 was computed.  net462 was computed.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen40 was computed.  tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (779)

Showing the top 5 NuGet packages that depend on DocumentFormat.OpenXml:

Package Downloads
ClosedXML

See release notes https://github.com/ClosedXML/ClosedXML/releases/tag/0.104.2 ClosedXML is a .NET library for reading, manipulating and writing Excel 2007+ (.xlsx, .xlsm) files. It aims to provide an intuitive and user-friendly interface to dealing with the underlying OpenXML API.
Omnia.Fx.NetCore

Package Description
Microting.eForm

Package Description
OpenXmlPowerTools

The Open XML PowerTools provides guidance and example code for programming with Open XML Documents (DOCX, XLSX, and PPTX). It is based on, and extends the functionality of the Open XML SDK. It supports scenarios such as: •Splitting DOCX/PPTX files into multiple files. •Combining multiple DOCX/PPTX files into a single file. •Populating content in template DOCX files with data from XML. •High-fidelity conversion of DOCX to HTML. •Searching and replacing content in DOCX/PPTX using regular expressions. •Managing tracked-revisions, including detecting tracked revisions, and accepting tracked revisions. •Updating Charts in DOCX/PPTX files, including updating cached data, as well as the embedded XLSX. •Retrieving metrics from DOCX files, including the hierarchy of styles used, the languages used, and the fonts used. •Writing XLSX files using far simpler code than directly writing the markup, including a streaming approach that enables writing XLSX files with millions of rows.
SpreadsheetLight

SpreadsheetLight is an open source Open XML spreadsheet .NET library written in C#, and is released under the MIT License. You can create new Open XML spreadsheets, or work with existing Open XML spreadsheets that are compatible with Microsoft Excel 2007/2010/2013 and LibreOffice Calc. No Office/Excel Interop needed. You do not need Microsoft Office/Excel to be installed.

GitHub repositories (63)

Showing the top 5 popular GitHub repositories that depend on DocumentFormat.OpenXml:

Repository Stars
microsoft/semantic-kernel
Integrate cutting-edge LLM technology quickly and easily into your apps
OrchardCMS/OrchardCore
Orchard Core is an open-source modular and multi-tenant application framework built with ASP.NET Core, and a content management system (CMS) built on top of that framework.
ClosedXML/ClosedXML
ClosedXML is a .NET library for reading, manipulating and writing Excel 2007+ (.xlsx, .xlsm) files. It aims to provide an intuitive and user-friendly interface to dealing with the underlying OpenXML API.
radzenhq/radzen-blazor
Radzen Blazor is a set of 90+ free native Blazor UI components packed with DataGrid, Scheduler, Charts and robust theming including Material design and FluentUI.
mini-software/MiniExcel
Fast, Low-Memory, Easy Excel .NET helper to import/export/template spreadsheet (support Linux, Mac)
Version Downloads Last updated
3.2.0 363 11/22/2024
3.1.1 419,051 10/16/2024
3.1.0 1,373,678 7/30/2024
3.0.2 3,070,176 3/14/2024
3.0.1 2,528,011 1/9/2024
3.0.0 1,192,720 11/15/2023
3.0.0-beta0003 23,126 9/5/2023
3.0.0-beta0002 20,071 6/14/2023
2.20.0 10,945,406 4/6/2023
2.19.0 5,148,452 12/14/2022
2.18.0 5,808,774 9/7/2022
2.17.1 3,356,048 6/30/2022
2.16.0 34,513,887 3/15/2022
2.15.0 5,464,546 12/17/2021
2.14.0 2,246,100 10/28/2021
2.14.0-beta0001 21,630 9/20/2021
2.13.1 3,333,817 8/18/2021
2.13.0 4,238,874 5/13/2021
2.13.0-beta0002 6,876 4/20/2021
2.13.0-beta0001 14,970 3/10/2021
2.12.3 3,343,263 2/24/2021
2.12.2 374,009 2/17/2021
2.12.1 2,079,793 1/11/2021
2.12.0 2,291,266 12/15/2020
2.11.3 7,991,568 7/17/2020
2.11.2 322,047 7/10/2020
2.11.1 8,306 7/10/2020
2.11.0 2,233,095 5/21/2020
2.11.0-beta0001 48,260 3/25/2020
2.10.1 4,947,626 2/28/2020
2.10.0 2,069,153 1/10/2020
2.10.0-beta0002 283,976 7/11/2019
2.10.0-beta0001 68,544 6/10/2019
2.9.1 10,253,995 3/13/2019
2.9.0 1,181,099 1/25/2019
2.8.1 8,751,980 1/6/2018
2.8.0 162,535 12/30/2017
2.7.2 49,243,804 6/7/2017
2.7.1 550,992 5/1/2017
2.5.0 13,414,124 8/4/2013
1.0.0 1,963,890 6/18/2011

# Changelog
All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).

## [3.0.0]

### Added
- Packages can now be saved on .NET Core and .NET 5+ if constructed with a path or stream (#1307).
- Packages can now support malformed URIs (such as relationships with a URI such as `mailto:person@`)

### Changed
- When validation finds incorrect part, it will now include the relationship type rather than a class name

### Removed
- .NET Standard 1.3 is no longer a supported platform. .NET Standard 2.0 is the lowest .NET Standard supported.
- Removed unused `SchemaAttrAttribute`
- Removed unused `ChildElementInfoAttribute`
- Removed `OpenXmlSimpleType.TextValue`. This property was never meant to be used externally
- Removed obsolete validation logic from v1 of the SDK
- Removed obsoleted methods from 2.x
- Removed mutable properties on OpenXmlAttribute and marked as `readonly`
- Removed `OpenXmlPackage.Close` in favor of Dispose (#1373)
- Removed `OpenXmlPackage.SaveAs` in favor of Clone (#1376)
- Removed `OpenXmlPackage.Package` property. A `OpenXmlPackage` is now backed by an internal (for now) type `IPackage` instead of `System.IO.Packaging.Package`

### Breaking change
- Core infrastructure is now contained in a new package DocumentFormat.OpenXml.Framework. Typed classes are still in DocumentFormat.OpenXml. This means that you may reference DocumentFormat.OpenXml and still compile the same types, but if you want a smaller package, you may rely on just the framework package.
- `EnumValue<T>` now is used to box a struct rather than a `System.Enum`. This allows us to enable behavior on it without resorting to reflection
- Methods on parts to add child parts (i.e. `AddImagePart`) are now implemented as extension methods off of a new marker interface `ISupportedRelationship<T>`
- Part type info enums (i.e. `ImagePartType`) is no longer an enum, but a static class to expose well-known part types as structs. Now any method to define a new content-type/extension pair can be called with the new `PartTypeInfo` struct that will contain the necessary information.
- `OpenXmlPackage.CanSave` is now an instance property (#1307)
- Removed `OpenXmlSettings.RelationshipErrorHandlerFactory` and associated types and replaced with a built-in mechanism to enable this
- `IdPartPair` is now a readonly struct rather than a class
- `IDisposableFeature` is now a part of the framework package and is available by default on a package or part.
- Renamed PartExtensionProvider to IPartExtensionFeature and reduced its surface area to only two methods (instead of a full Dictionary<,>). The property to access this off of OpenXmlPackage has been removed, but may be accessed via `Features.Get<IPartExtensionFeature>()` if needed.
- `OpenXmlPart`/`OpenXmlContainer`/`OpenXmlPackage` and derived types now have internal constructors (these had internal abstract methods so most likely weren't subclassed externally)
- `OpenXmlElementList` is now a struct that implements `IEnumerable<OpenXmlElement>` and `IReadOnlyList<OpenXmlElement>` (where available)
- Individual implementations of `OpenXmlPartReader` are available now for each package type (i.e. `WordprocessingDocumentPartReader`, `SpreadsheetDocumentPartReader`, `PresentationDocumentPartReader`), and the previous `TypedOpenXmlPartReader` has been removed.

## [2.20.0]

### Added
- Added DocumentFormat.OpenXml.Office.Drawing.Y2022.ImageFormula namespace
- Added DocumentFormat.OpenXml.Office.Word.Y2023.WordML.Word16DU namespace

### Changed
- Marked `OpenXmlSimpleType.TextValue` as obsolete. This property was never meant to be used externally (#1284)
- Marked `OpenXmlPackage.Package` as obsolete. This will be an implementation detail in future versions and won't be accessible (#1306)
- Marked `OpenXmlPackage.Close` as obsolete. This will be removed in a later release, use Dispose instead (#1371)
- Marked `OpenXmlPackage.SaveAs` as obsolete as it will be removed in a future version (#1378)

### Fixed
- Fixed incorrect file extensions for vbaProject files (#1292)
- Fixed incorrect file extensions for ImagePart (#1305)
- Fixed incorrect casing for customXml (#1351)
- Fixed AddEmbeddedPackagePart to allow correct extensions for various content types (#1388)

## [2.19.0] - 2022-12-14

### Added
- .NET 6 target with support for trimming (#1243, #1240)
- Added DocumentFormat.OpenXml.Office.SpreadSheetML.Y2022.PivotRichData namespace
- Added DocumentFormat.OpenXml.Office.PowerPoint.Y2019.Main.Command namespace
- Added DocumentFormat.OpenXml.Office.PowerPoint.Y2022.Main.Command namespace
- Added Child RichDataPivotCacheGuid to DocumentFormat.OpenXml.Office2010.Excel.PivotCacheDefinition

### Fixed
- Removed reflection usage where possible (#1240)
- Fixed issue where some URIs might be changed when cloning or creating copy (#1234)
- Fixed issue in FlatOpc generation that would not read the full stream on .NET 6+ (#1232)
- Fixed issue where restored relationships wouldn't load correctly (#1207)

## [2.18.0] 2022-09-06

### Added
- Added DocumentFormat.OpenXml.Office.SpreadSheetML.Y2021.ExtLinks2021 namespace (#1196)
- Added durableId attribute to DocumentFormat.OpenXml.Wordprocessing.NumberingPictureBullet (#1196)
- Added few base classes for typed elements, parts, and packages (#1185)

### Changed
- Adjusted LICENSE.md to conform to .NET Foundation requirements (#1194)
- Miscellaneous changes for better perf for internal services

## [2.17.1] - 2022-06-28

### Removed
- Removed the preview namespace DocumentFormat.OpenXml.Office.Comments.Y2020.Reactions because this namespace will currently create invalid documents.

### Fixed
- Restored the PowerPointCommentPart relationship to PresentationPart.

### Deprecated
- The relationship between the PowerPointCommentPart and the PresentationPart is deprecated and will be removed in a future version.

## [2.17.0] - Unreleased

### Added
- Added DocumentFormat.OpenXml.Office.Comments.Y2020.Reactions namespace (#1151)
- Added DocumentFormat.OpenXml.Office.SpreadSheetML.Y2022.PivotVersionInfo namespace (#1151)

### Fixed
- Moved PowerPointCommentPart relationship to SlidePart (#1137)

### Updated
- Removed public API analyzers in favor of EnablePackageValidation (#1154)

## [2.16.0] - 2022-03-14

### Added
- Added method `OpenXmlPart.UnloadRootElement` that will unload the root element if it is loaded (#1126)

### Updated
- Schema code generation was moved to the SDK project using C# code generators

Thanks to the following for their contribution:

@f1nzer

## [2.15.0] - 2021-12-16

### Added
- Added samples for strongly typed classes and Linq-to-XML in the `./samples` directory (#1101, #1087)
- Shipping additional libraries for some additional functionality in `DocumentFormat.OpenXml.Features` and `DocumentFormat.OpenXml.Linq`. See documentation in repo for additional details.
- Added extension method to support getting image part type (#1082)
- Added generated classes and `FileFormatVersions.Microsoft365` for new subscription model types and constraints (#1097).

### Fixed
- Fixed issue for changed mime type `model/gltf.binary` (#1069)
- DocumentFormat.OpenXml.Office.Drawing.ShapeTree is now available only in Office 2010 and above, not 2007.
- Correctly serialize `new CellValue(bool)` values (#1070)
- Updated known namespaces to be generated via an in-repo source generator (#1092)
- Some documentation issues around `FileFormatVersions` enum

Thanks to the following for their contributions:

@ThomasBarnekow
@stevenhansen
@JaimeStill
@jnyrup

## [2.14.0] - 2021-10-28

### Added
- Added generated classes for Office 2021 types and constraints (#1030)
- Added `Features` property to `OpenXmlPartContainer` and `OpenXmlElement` to enable a per-part or per-document state storage
- Added public constructors for `XmlPath` (#1013)
- Added parts for Rich Data types (#1002)

Thanks to the following for their contributions:

@rmboggs
@ThomasBarnekow

## [2.14.0-beta1] - 2021-09-20

### Added
- Added `Features` property to `OpenXmlPartContainer` and `OpenXmlElement` to enable a per-part or per-document state storage
- Added public constructors for `XmlPath` (#1013)
- Added parts for Rich Data types (#1002)
- Added methods to generate unique paragraph ids (#1000)
- Added generated classes for Office 2021 types and constraints (#1030)

Thanks to the following for their contributions:

@rmboggs
@ThomasBarnekow

## [2.13.1] - 2021-08-17

### Fixed
- Fixed some nullability annotations that were incorrectly defined (#953, #955)
- Fixed issue that would dispose a `TextReader` when creating an `XmlReader` under certain circumstances (#940)
- Fixed a documentation type (#937)
- Fixed an issue with adding additional children to data parts (#934)
- Replaced some documentation entries that were generic values with helpful comments (#992)
- Fixed a regression in AddDataPartRelationship (#954)

Thanks to the following for their contributions:

@ThomasBarnekow
@sorensenmatias
@lklein53
@lindexi

## [2.13.0] - 2021-05-13

### Added
- Additional O19 types to match Open Specifications (#916)
- Added generated classes for Office 2019 types and constraints (#882)
- Added nullability attributes (#840, #849)
- Added overload for `OpenXmlPartReader` and `OpenXmlReader.Create(...)` to ignore whitespace (#857)
- Added `HexBinaryValue.TryGetBytes(...)` and `HexBinaryValue.Create(byte[])` to manage the encoding and decoding of bytes (#867)
- Implemented `IEquatable<IdPartPair>` on `IdPartPair` to fix equality implementation there and obsoleted setters (#871)

### Fixed
- Fixed serialization of `CellValue` constructors to use invariant cultures (#903)
- Fixed parsing to allow exponents for numeric cell values (#901)
- Fixed massive performance bottleneck when `UniqueAttributeValueConstraint` is involved (#924)

### Deprecated
- Deprecated Office2013.Word.Person.Contact property. It no longer persists and will be removed in a future version (#912)

Thanks to the following for their contributions:

@lklein53  
@igitur

## [2.13.0-beta2] - 2021-04-20

### Added
- Additional O19 types to match Open Specifications (#916)

### Deprecated
- Deprecated Office2013.Word.Person.Contact property. It no longer persists and will be removed in a future version (#912)

## [2.13.0-beta1] - 2021-03-09

### Added
- Added nullability attributes (#840, #849)
- Added overload for `OpenXmlPartReader` and `OpenXmlReader.Create(...)` to ignore whitespace (#857)
- Added `HexBinaryValue.TryGetBytes(...)` and `HexBinaryValue.Create(byte[])` to manage the encoding and decoding of bytes (#867)
- Implemented `IEquatable<IdPartPair>` on `IdPartPair` to fix equality implementation there and obsoleted setters (#871)
- Added generated classes for Office 2019 types and constraints (#882)

### Fixed
- Fixed serialization of `CellValue` constructors to use invariant cultures (#903)
- Fixed parsing to allow exponents for numeric cell values (#901)

## [2.12.3] - 2021-02-24

### Fixed
- Fixed issue where `CellValue` may validate incorrectly for boolean values (#890)

## [2.12.2] - 2021-02-16

### Fixed
- Fixed issue where `OpenSettings.RelationshipErrorHandlerFactory` creates invalid XML if the resulting URI is smaller than the input (#883)

## [2.12.1] - 2021-01-11

### Fixed
- Fixed bug where properties on `OpenXmlCompositeElement` instances could not be set to null to remove element (#850)
- Fixed `OpenXmlElement.RawOuterXml` to properly set null values without throwing (#818)
- Allow rewriting of all malformed URIs regardless of target value (#835)

## [2.12.0] - 2020-12-09

### Added
- Added `OpenSettings.RelationshipErrorHandlerFactory` to provide a way to handle URIs that break parsing documents with malformed links (#793)
- Added `OpenXmlCompositeElement.AddChild(OpenXmlElement)` to add children in the correct order per schema (#774)
- Added `SmartTagClean` and `SmartTagId` in place of `SmtClean` and `SmtId` (#747)
- Added `OpenXmlValidator.Validate(..., CancellationToken)` overrides to allow easier cancellation of long running validation on .NET 4.0+ (#773)
- Added overloads for `CellValue` to take `decimal`, `double`, and `int`, as well as convenience methods to parse them (#782)
- Added validation for `CellType` for numbers and date formats (#782)
- Added `OpenXmlReader.GetLineInfo()` to retrieve `IXmlLineInfo` of the underlying reader if available (#804)

### Fixed
- Fixed exception that would be thrown if attempting to save a document as FlatOPC if it contains SVG files (#822)
- Added `SchemaAttrAttribute` attributes back for backwards compatibility (#825)

### Removed
- Removed explicit reference to `System.IO.Packaging` on .NET 4.6 builds (#774)

## [2.11.3] - 2020-07-17
### Fixed
- Fixed massive performance bottleneck when `IndexReferenceConstraint` and `ReferenceExistConstraint` are involved (#763)
- Fixed `CellValue` to only include three most signficant digits on second fractions to correct issue loading dates (#741)
- Fixed a couple of validation indexing errors that might cause erroneous validation errors (#767)
- Updated internal validation system to not use recursion, allowing for better short-circuiting (#766)

## [2.11.2] - 2020-07-10

### Fixed
- Fixed broken source link (#749)
- Ensured compilation is deterministic (#749)
- Removed extra file in NuGet package (#749)

## [2.11.1] - 2020-07-10

### Fixed
- Ensure .NET Framework builds pass PEVerify (#744)
- `OpenXmlPartContainer.DeletePart` no longer throws an exception if there isn't a match for the identifier given (#740)
- Mark obsolete members to not show up with Intellisense (#745)
- Fixed issue with `AttributeRequiredConditionToValue` semantic constraint where validation could fail on correct input (#746)

## [2.11.0] - 2020-05-21
### Added
- Added `FileFormatVersions.2019` enum (#695)
- Added `ChartSpace` and chart elements for the new 2016 namespaces. This allows the connecting pieces for building a chart part with chart styles like "Sunburst" (#687).
- Added `OpenXmlElementFunctionalExtensions.With(...)` extension methods, which offer flexible means for constructing `OpenXmlElement` instances in the context of pure functional transformations (#679)
- Added minimum Office versions for enum types and values (#707)
- Added additional `CompatSettingNameValues` values: `UseWord2013TrackBottomHyphenation`, `AllowHyphenationAtTrackBottom`, and `AllowTextAfterFloatingTableBreak` (#706)
- Added gfxdata attribue to Arc, Curve, Line, PolyLine, Group, Image, Oval, Rect, and RoundRect shape complex types per MS-OI29500 2.1.1783-1799 (#709)
- Added `OpenXmlPartContainer.TryGetPartById` to enable child part retrieval without exception if it does not exist (#714)
- Added `OpenXmlPackage.StrictRelationshipFound` property that indicates whether this package contains Transitional relationships converted from Strict (#716)

### Fixed
- Custom derived parts did not inherit known parts from its parent, causing failure when adding parts (#722)

### Changed
- Marked the property setters in `OpenXmlAttribute` as obsolete as structs should not have mutable state (#698)

## [2.10.1] - 2020-02-28
### Fixed
- Ensured attributes are available when `OpenXmlElement` is initialized with outer XML (#684, #692)
- Some documentation errors (#681)
- Removed state that made it non-thread safe to validate elements under certain conditions (#686)
- Correctly inserts strongly-typed elements before known elements that are not strongly-typed (#690)

## [2.10.0] - 2020-01-10
### Added
- Added initial Office 2016 support, including `FileFormatVersion.Office2016`, `ExtendedChartPart` and other new schema elements (#586)
- Added .NET Standard 2.0 target (#587)
- Included symbols support for debugging (#650)
- Exposed `IXmlNamespaceResolver` from `XmlPath` instead of formatted list of strings to expose namespace/prefix mapping (#536)
- Implemented `IComparable<T>` and `IEquatable<T>` on `OpenXmlComparableSimpleValue` to allow comparisons without boxing (#550)
- Added `OpenXmlPackage.RootPart` to easily access the root part on any package (#661)

### Changed
- Updated to v4.7.0 of System.IO.Packaging which brings in a number of perf fixes (#660)
- Consolidated data for element children/properties to reduce duplication (#540, #547, #548)
- Replaced opaque binary data for element children constraints with declarative model (#603)
- A number of performance fixes to minimize allocations where possible
- 20% size reduction from 5.5mb to 4.3mb
- The validation subsystem went through a drastic redesign. This may cause changes in what errors are reported.

### Fixed
- Fixed some documentation inconsistencies (#582)
- Fixed `ToFlatOpcDocument`, `ToFlatOpcString`, `FromFlatOpcDocument`, and `FromFlatOpcString` to correctly process Alternative Format Import Parts, or "altChunk parts" (#659)

## [2.9.1] - 2019-03-13
### Changed
- Added a workaround for a .NET Native compiler issue that doesn't support calling Marshal.SizeOf<T> with a struct that contains auto-implemented properties (#569)
- Fixed a documentation error (#528)

## [2.9.0] - 2018-06-08
### Added
- `ListValue` now implements `IEnumerable<T>` (#385)
- Added a `WebExtension.Frozen` and obsoleted misspelled `Fronzen` property (#460)
- Added an `OpenXmlPackage.CanSave` property that indicates whether a platform supports saving without closing the package (#468)
- Simple types (except `EnumValue` and `ListValue`) now implement `IComparable<T>` and `IEquatable<T>` (#487)

### Changed
- Removed state that was carried in validators that would hold onto packages when not in use (#390)
- `EnumSimpleType` parsing was improved and uses less allocations and caches for future use (#408)
- Fixed a number of spelling mistakes in documentation (#462)
- When calling `OpenXmlPackage.Save` on .NET Framework, the package is now flushed to the stream (#468)
- Fixed race condition while performing strict translation of attributes (#480)
- Schema data for validation uses a more compact format leading to a reduction in dll size and performance improvements for loading (#482, #483)
- A number of APIs are marked as obsolete as they have simple workarounds and will be removed in the next major change
- Fixed some constraint values for validation that contained Office 2007, even when it was only supported in later versions
- Updated `System.IO.Packaging` to 4.5.0 which fixes some issues on Xamarin platforms as well as minimizes dependencies on .NET Framework

## [2.8.1] - 2018-01-03
### Changed
- Corrected package license file reference to show updated MIT License

## [2.8.0] - 2017-12-28
### Added
- Default runtime directive for better .NET Native support.

### Changed
- Fixed part saving to be encoded with UTF8 but no byte order mark. This caused some renderers to not be able to open the generated document.
- Fixed exceptions thrown when errors are encountered while opening packages to be consistent across platforms.
- Fixed issue on Mono platforms using System.IO.Packaging NuGet package (Xamarin, etc) when creating a document.
- Fixed manual saving of a package when autosave is false.
- Fixed schema constraint data and standardized serialization across platforms.
- Upgraded to `System.IO.Packaging` version 4.4.0 which fixes some consistency with .NET Framework in opening packages.

## [2.7.2] - 2017-06-06
### Added
- Package now supports .NET 3.5 and .NET 4.0 in addition to .NET Standard 1.3 and .NET Framework 4.6

### Changed
- Fixed issue where assembly version wasn't set in assembly.

## [2.7.1] - 2017-01-31
### Changed
- Fixed crash when validation is invoked on .NET Framework with strong-naming enforced.

## [2.7.0] - 2017-01-24
### Added
- SDK now  supports .NET Standard 1.3

### Changed
- Moved to using System.IO.Packaging from dotnet/corefx for .NET Standard 1.3 and WindowsBase for .NET 4.5.
- Cleaned up project build system to use .NET CLI.

## [2.6.1] - 2016-01-15
### Added
- Added hundreds of XUnit tests. There are now a total of 1333 tests. They take about 20 minutes to run, so be patient.

## [2.6.0] - 2015-06-29
### Added
- Incorporated a replacement `System.IO.Packaging` that fixes some serious (but exceptional) bugs found in the WindowsBase implementation

[3.0.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.20.0...v3.0.0
[2.20.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.19.0...v2.20.0
[2.19.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.18.0...v2.19.0
[2.18.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.17.1...v2.18.0
[2.17.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.17.0...v2.17.1
[2.17.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.16.0...v2.17.0
[2.16.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.15.0...v2.16.0
[2.15.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.14.0...v2.15.0
[2.14.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.14.0-beta1...v2.14.0
[2.14.0-beta1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.13.1...v2.14.0-beta1
[2.13.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.13.0...v2.13.1
[2.13.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.13.0...v2.13.0
[2.13.0-beta2]: https://github.com/dotnet/Open-XML-SDK/compare/v2.13.0-beta2...v2.13.0-beta2
[2.13.0-beta1]: https://github.com/dotnet/Open-XML-SDK/compare/2.12.3...v2.13.0-beta1
[2.12.3]: https://github.com/dotnet/Open-XML-SDK/compare/v2.12.3...v2.12.1
[2.12.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.12.1...v2.12.0
[2.12.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.12.0...v2.11.3
[2.11.3]: https://github.com/dotnet/Open-XML-SDK/compare/v2.11.3...v2.11.2
[2.11.2]: https://github.com/dotnet/Open-XML-SDK/compare/v2.11.2...v2.11.1
[2.11.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.11.1...v2.11.0
[2.11.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.11.0...v2.10.1
[2.10.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.10.1...v2.10.0
[2.10.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.10.0...v2.9.1
[2.9.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.9.1...v2.9.0
[2.9.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.9.0...v2.8.1
[2.8.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.8.1...v2.8.0
[2.8.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.8.0...v2.7.2
[2.7.2]: https://github.com/dotnet/Open-XML-SDK/compare/v2.7.1...v2.7.2
[2.7.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.7.0...v2.7.1
[2.7.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.6.1...v2.7.0
[2.6.1]: https://github.com/dotnet/Open-XML-SDK/compare/v2.6.0...v2.6.1
[2.6.0]: https://github.com/dotnet/Open-XML-SDK/compare/v2.5.0...v2.6.0