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/***************************************************************************\
*
* File: ProvideValueServiceProvider.cs
*
* ServiceProvider class that is passed into MarkupExtensions.ProvideValue method
* that understands the ParserContext.
*
* Copyright (C) 2006 by Microsoft Corporation. All rights reserved.
*
\***************************************************************************/
using System;
using System.Windows;
using System.Windows.Media;
using System.Diagnostics;
namespace System.Windows.Markup
{
/// <summary>
/// Base class for all Xaml markup extensions.
/// </summary>
internal class ProvideValueServiceProvider : IServiceProvider, IProvideValueTarget, IXamlTypeResolver, IUriContext, IFreezeFreezables
{
// Construction
internal ProvideValueServiceProvider(ParserContext context)
{
_context = context;
}
internal ProvideValueServiceProvider()
{
}
// Set the TargetObject/Property (for use by IProvideValueTarget).
internal void SetData(object targetObject, object targetProperty)
{
_targetObject = targetObject;
_targetProperty = targetProperty;
}
// Clear the TargetObject/Property (after a call to ProvideValue)
internal void ClearData()
{
_targetObject = _targetProperty = null;
}
// IXamlTypeResolver implementation
Type IXamlTypeResolver.Resolve(string qualifiedTypeName) // E.g. foo:Class
{
return _context.XamlTypeMapper.GetTypeFromBaseString(qualifiedTypeName, _context, true);
}
// IProvideValueTarget implementation
object IProvideValueTarget.TargetObject
{
get { return _targetObject; }
}
object IProvideValueTarget.TargetProperty
{
get { return _targetProperty; }
}
// IUriContext implementation
Uri IUriContext.BaseUri
{
get { return _context.BaseUri; }
set { throw new NotSupportedException(SR.Get(SRID.ParserProvideValueCantSetUri)); }
}
bool IFreezeFreezables.FreezeFreezables
{
get
{
return _context.FreezeFreezables;
}
}
bool IFreezeFreezables.TryFreeze(string value, Freezable freezable)
{
return _context.TryCacheFreezable(value, freezable);
}
Freezable IFreezeFreezables.TryGetFreezable(string value)
{
return _context.TryGetFreezable(value);
}
// IServiceProvider implementation (this is the way to get to the
// above interface implementations).
public object GetService(Type service)
{
// IProvideValueTarget is the only implementation that
// doesn't need the ParserContext
if( service == typeof(IProvideValueTarget))
{
return this as IProvideValueTarget;
}
if( _context != null )
{
if( service == typeof(IXamlTypeResolver))
{
return this as IXamlTypeResolver;
}
else if( service == typeof(IUriContext))
{
return this as IUriContext;
}
else if (service == typeof(IFreezeFreezables))
{
return this as IFreezeFreezables;
}
}
return null;
}
// Data
private ParserContext _context = null;
private object _targetObject = null;
private object _targetProperty = null;
}
}
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