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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
//---------------------------------------------------------------------------
using System;
using System.Windows; // For ExceptionStringTable
using System.Xml; // For DOM objects
using System.Diagnostics; // For Assert
using System.Globalization; // For CultureInfo
namespace MS.Internal.IO.Packaging
{
internal class XmlFixedPageInfo : MS.Internal.FixedPageInfo
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Initialize object from DOM node.
/// </summary>
/// <remarks>
/// The DOM node is assumed to be a XAML FixedPage element. Its namespace URI
/// is subsequently used to look for its nested Glyphs elements (see private property NodeList).
/// </remarks>
internal XmlFixedPageInfo(XmlNode fixedPageNode)
{
_pageNode = fixedPageNode;
Debug.Assert(_pageNode != null);
if (_pageNode.LocalName != _fixedPageName || _pageNode.NamespaceURI != ElementTableKey.FixedMarkupNamespace)
{
throw new ArgumentException(SR.Get(SRID.UnexpectedXmlNodeInXmlFixedPageInfoConstructor,
_pageNode.NamespaceURI, _pageNode.LocalName,
ElementTableKey.FixedMarkupNamespace, _fixedPageName));
}
}
#endregion Constructors
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
/// <summary>
/// Get the glyph run at zero-based position 'position'.
/// </summary>
/// <remarks>
/// Returns null for a nonexistent position. No exception raised.
/// </remarks>
internal override GlyphRunInfo GlyphRunAtPosition(int position)
{
if (position < 0 || position >= GlyphRunList.Length)
{
return null;
}
if (GlyphRunList[position] == null)
{
GlyphRunList[position] = new XmlGlyphRunInfo(NodeList[position]);
}
return GlyphRunList[position];
}
#endregion Internal Methods
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
#region Internal Properties
/// <summary>
/// Indicates the number of glyph runs on the page.
/// </summary>
internal override int GlyphRunCount
{
get
{
return GlyphRunList.Length;
}
}
#endregion Internal Properties
//------------------------------------------------------
//
// Private Properties
//
//------------------------------------------------------
#region Private Properties
/// <summary>
/// Lazily initialize _glyphRunList, an array of XmlGlyphInfo objects,
/// using the NodeList private property.
/// </summary>
/// <remarks>
/// When using Visual Studio to step through code using this property, make sure the option
/// "Allow property evaluation in variables windows" is unchecked.
/// </remarks>
private XmlGlyphRunInfo[] GlyphRunList
{
get
{
if (_glyphRunList == null)
{
_glyphRunList = new XmlGlyphRunInfo[NodeList.Count];
}
return _glyphRunList;
}
}
/// <summary>
/// Lazily initialize the list of Glyphs elements on the page using XPath.
/// </summary>
/// <remarks>
/// When using Visual Studio to step through code using this property, make sure the option
/// "Allow property evaluation in variables windows" is unchecked.
/// </remarks>
private XmlNodeList NodeList
{
get
{
if (_nodeList == null)
{
string glyphRunQuery = String.Format(CultureInfo.InvariantCulture, ".//*[namespace-uri()='{0}' and local-name()='{1}']",
ElementTableKey.FixedMarkupNamespace,
_glyphRunName);
_nodeList = _pageNode.SelectNodes(glyphRunQuery);
}
return _nodeList;
}
}
#endregion Private Properties
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
#region Constants
private const string _fixedPageName = "FixedPage";
private const string _glyphRunName = "Glyphs";
#endregion Constants
private XmlNode _pageNode;
private XmlNodeList _nodeList = null;
private XmlGlyphRunInfo[] _glyphRunList = null;
#endregion Private Fields
}
}
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