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// Copyright (C) Microsoft Corporation. All rights reserved.
using System.ComponentModel;
using System.Globalization;
using System.Windows;
using System.Collections.Generic;
using System.Xaml;
namespace System.Windows.Markup
{
/// <summary>
/// Type converter for RoutedEvent type
/// </summary>
public sealed class RoutedEventConverter : TypeConverter
{
/// <summary>
/// Whether we can convert from a given type - this class only converts from string
/// </summary>
public override bool CanConvertFrom(ITypeDescriptorContext typeDescriptorContext, Type sourceType)
{
// We can only convert from a string and that too only if we have all the contextual information
// Note: Sometimes even the serializer calls CanConvertFrom in order
// to determine if it is a valid converter to use for serialization.
if (sourceType == typeof(string))
{
return true;
}
return false;
}
/// <summary>
/// Whether we can convert to a given type - this class only converts to string
/// </summary>
public override bool CanConvertTo(ITypeDescriptorContext typeDescriptorContext, Type destinationType)
{
return false;
}
/// <summary>
/// Convert a string like "Button.Click" into the corresponding RoutedEvent
/// </summary>
public override object ConvertFrom(ITypeDescriptorContext typeDescriptorContext,
CultureInfo cultureInfo,
object source)
{
string routedEventName = source as string;
RoutedEvent routedEvent = null;
if (routedEventName != null)
{
routedEventName = routedEventName.Trim();
IServiceProvider serviceProvider = typeDescriptorContext as IServiceProvider;
if (serviceProvider != null)
{
IXamlTypeResolver resolver = serviceProvider.GetService(typeof(IXamlTypeResolver)) as IXamlTypeResolver;
Type type = null;
if (resolver != null)
{
// Verify that there's at least one period. (A simple
// but not foolproof check for "[class].[event]")
int lastIndex = routedEventName.IndexOf('.');
if (lastIndex != -1)
{
string typeName = routedEventName.Substring(0, lastIndex);
routedEventName = routedEventName.Substring(lastIndex + 1);
type = resolver.Resolve(typeName);
}
}
if (type == null)
{
IXamlSchemaContextProvider schemaContextProvider = (typeDescriptorContext.
GetService(typeof(IXamlSchemaContextProvider))
as IXamlSchemaContextProvider);
IAmbientProvider iapp = serviceProvider.GetService(typeof(IAmbientProvider)) as IAmbientProvider;
if (schemaContextProvider != null && iapp != null)
{
XamlSchemaContext schemaContext = schemaContextProvider.SchemaContext;
XamlType styleXType = schemaContext.GetXamlType(typeof(Style));
List<XamlType> ceilingTypes = new List<XamlType>();
ceilingTypes.Add(styleXType);
XamlMember styleTargetType = styleXType.GetMember("TargetType");
AmbientPropertyValue firstAmbientValue = iapp.GetFirstAmbientValue(ceilingTypes, styleTargetType);
if (firstAmbientValue != null)
{
type = firstAmbientValue.Value as Type;
}
if (type == null)
{
type = typeof(FrameworkElement);
}
}
}
if (type != null)
{
Type currentType = type;
// Force load the Statics by walking up the hierarchy and running class constructors
while (null != currentType)
{
MS.Internal.WindowsBase.SecurityHelper.RunClassConstructor(currentType);
currentType = currentType.BaseType;
}
routedEvent = EventManager.GetRoutedEventFromName(routedEventName, type);
}
}
}
if (routedEvent == null)
{
// Falling through here means we are unable to perform the conversion.
throw GetConvertFromException(source);
}
return routedEvent;
}
/// <summary>
/// Convert a RoutedEventID into a XAML string like "Button.Click"
/// </summary>
public override object ConvertTo(ITypeDescriptorContext typeDescriptorContext,
CultureInfo cultureInfo,
object value,
Type destinationType)
{
if (value == null)
{
throw new ArgumentNullException("value");
}
else if (destinationType == null)
{
throw new ArgumentNullException("destinationType");
}
else
{
throw GetConvertToException(value, destinationType);
}
}
// This routine is copied from TemplateBamlRecordReader. This functionality
// is planned to be part of the utilities exposed by the parser, eliminating
// the need to duplicate code. See task #18279
private string ExtractNamespaceString(ref string nameString, ParserContext parserContext)
{
// The colon is what we look for to determine if there's a namespace prefix specifier.
int nsIndex = nameString.IndexOf(':');
string nsPrefix = string.Empty;
if (nsIndex != -1)
{
// Found a namespace prefix separator, so create replacement propertyName.
// String processing - split "foons" from "BarClass.BazProp"
nsPrefix = nameString.Substring(0, nsIndex);
nameString = nameString.Substring(nsIndex + 1);
}
// Find the namespace, even if its the default one
string namespaceURI = parserContext.XmlnsDictionary[nsPrefix];
if (namespaceURI == null)
{
throw new ArgumentException(SR.Get(SRID.ParserPrefixNSProperty, nsPrefix, nameString));
}
return namespaceURI;
}
}
}
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