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//---------------------------------------------------------------------------
//
// <copyright file="XmlFixedPageInfo.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
// Description:
// Implements a DOM-based subclass of the FixedPageInfo abstract class.
// The class functions as an array of XmlGlyphRunInfo's in markup order.
//
// History:
// 05/06/2004: JohnLarc: Initial implementation
// 10/31/2005: JohnLarc: Removed GDI-aware implementations. To restore them, run
// 'sd labelsync -l XmlGlyphRunInfo'.
//---------------------------------------------------------------------------
using System;
using System.Xml; // For DOM objects
using System.Diagnostics; // For Assert
using System.Globalization; // For CultureInfo
using System.Windows; // For ExceptionStringTable
using Windows = System.Windows; // For Windows.Point (as distinct from System.Drawing.Point)
using System.Windows.Markup; // For XmlLanguage
namespace MS.Internal.IO.Packaging
{
/// <summary>
/// DOM-based implementation of the abstract class GlyphRunInfo.
/// </summary>
internal class XmlGlyphRunInfo : MS.Internal.GlyphRunInfo
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Initialize from a DOM object.
/// </summary>
internal XmlGlyphRunInfo(XmlNode glyphsNode)
{
_glyphsNode = glyphsNode as XmlElement;
// Assert that XmlFixedPageInfo (only caller) has correctly identified glyph runs
// prior to invoking this constructor.
Debug.Assert(_glyphsNode != null
&& String.CompareOrdinal(_glyphsNode.LocalName, _glyphRunName) == 0
&& String.CompareOrdinal(_glyphsNode.NamespaceURI, ElementTableKey.FixedMarkupNamespace) == 0);
}
#endregion Constructors
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
#region Internal Properties
/// <summary>
/// The start point of the segment [StartPosition, EndPosition],
/// which runs along the baseline of the glyph run.
/// </summary>
/// <remarks>
/// The point is given in page coordinates.
/// double.NaN can be returned in either coordinate when the input glyph run is invalid.
/// </remarks>
internal override Windows.Point StartPosition
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// The end point of the segment [StartPosition, EndPosition],
/// which runs along the baseline of the glyph run.
/// </summary>
/// <remarks>
/// The point is given in page coordinates.
/// double.NaN can be returned in either coordinate when the input glyph run is invalid.
/// </remarks>
internal override Windows.Point EndPosition
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// The font width in ems.
/// </summary>
/// <remarks>
/// This is provided for the purpose of evaluating distances along the baseline OR a perpendicular
/// to the baseline.
/// When a font is displayed sideways, what is given here is still the width of the font.
/// It is up to the client code to decide whether to use the width or height for measuring
/// distances between glyph runs.
///
/// NaN can be returned if the markup is invalid.
/// </remarks>
internal override double WidthEmFontSize
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// The font height in ems.
/// </summary>
/// <remarks>
/// This is provided for the purpose of evaluating distances along the baseline OR a perpendicular
/// to the baseline.
/// When a font is displayed sideways, what is given here is still the height of the font.
/// It is up to the client code to decide whether to use the width or height for measuring
/// deviations from the current baseline.
///
/// NaN can be returned if the markup is invalid.
/// </remarks>
internal override double HeightEmFontSize
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// Whether glyphs are individually rotated 90 degrees (so as to face downwards in vertical text layout).
/// </summary>
/// <remarks>
/// This feature is designed for ideograms and should not make sense for latin characters.
/// </remarks>
internal override bool GlyphsHaveSidewaysOrientation
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// 0 for left-to-right and 1 for right-to-left.
/// </summary>
/// <remarks>
/// 0 is assumed if the attribute value is absent or unexpected.
/// </remarks>
internal override int BidiLevel
{
get
{
throw new NotSupportedException(SR.Get(SRID.XmlGlyphRunInfoIsNonGraphic));
}
}
/// <summary>
/// The glyph run's language id.
/// </summary>
/// <remarks>
/// The language ID is typed as unsigned for easier interop marshalling, since the win32 LCID type (as defined in WinNT.h) is a DWORD.
/// </remarks>
internal override uint LanguageID
{
get
{
if (_languageID == null)
{
for (XmlElement currentNode = _glyphsNode;
currentNode != null && _languageID == null;
currentNode = (currentNode.ParentNode as XmlElement))
{
string languageString = currentNode.GetAttribute(_xmlLangAttribute);
if (languageString != null && languageString.Length > 0)
{
// We need to handle languageString "und" specially.
// we should set language ID to zero.
// That's what the Indexing Search team told us to do.
// There's no CultureInfo for "und".
// CultureInfo("und") will cause an error.
if (string.CompareOrdinal(languageString.ToUpperInvariant(), _undeterminedLanguageStringUpper) == 0)
{
_languageID = 0;
}
else
{
// Here we use XmlLanguage class to help us get the most
// compatible culture from the languageString.
//
// In the case that languageString and its variants do not match
// any known language string in the table, we will get InvariantCulture
// from GetCompatibleCulture().
//
// In the case that languageString is invalid (e.g. non-ascii string),
// the GetLanguage() method will throw an exception and we will give
// up filtering this part.
XmlLanguage lang = XmlLanguage.GetLanguage(languageString);
CultureInfo cultureInfo = lang.GetCompatibleCulture();
_languageID = checked((uint)cultureInfo.LCID);
}
}
}
// If we cannot set the language ID in the previous logic, that means the
// language string is missing and we should default the culture to be
// InvariantCulture.
// Note: XamlFilter.GetCurrentLcid is a private method that also has
// similar logic and will default to CultureInfo.InvariantCulture.LCID
// CultureInfo.InvariantCulture will never be null
if(_languageID == null)
_languageID = checked((uint)CultureInfo.InvariantCulture.LCID);
}
// Cast Nullable<> into value type.
return (uint) _languageID;
}
}
/// <summary>
/// The glyph run's contents as a string of unicode symbols.
/// If the unicode attribute is missing in the markup then an empty string is returned.
/// </summary>
internal override string UnicodeString
{
get
{
if (_unicodeString == null)
{
_unicodeString = _glyphsNode.GetAttribute(_unicodeStringAttribute);
}
return _unicodeString;
}
}
#endregion Internal Properties
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
#region Constants
private const string _glyphRunName = "Glyphs";
private const string _xmlLangAttribute = "xml:lang";
private const string _unicodeStringAttribute = "UnicodeString";
// The undetermined language string can be "und" or "UND". We always convert strings
// to uppercase for case-insensitive comparison, so we store an uppercase version here.
private const string _undeterminedLanguageStringUpper = "UND";
private XmlElement _glyphsNode = null;
private string _unicodeString = null;
private Nullable<uint> _languageID = null;
#endregion Private Fields
}
#endregion NativeMethods
}
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