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//-----------------------------------------------------------------------
//
// Microsoft Windows Client Platform
// Copyright (C) Microsoft Corporation, 2005
//
// File: CommandValueSerializer.cs
//
// Contents: ValueSerializer for the ICommand interface
//
// Created: 04/28/2005 Microsoft
//
//------------------------------------------------------------------------
namespace System.Windows.Input
{
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Markup;
using System.Windows.Documents; // EditingCommands
using System.Reflection;
internal class CommandValueSerializer : ValueSerializer
{
public override bool CanConvertToString(object value, IValueSerializerContext context)
{
if (context == null || context.GetValueSerializerFor(typeof(Type)) == null)
return false;
// Can only convert routed commands
RoutedCommand command = value as RoutedCommand;
if (command == null || command.OwnerType == null)
{
return false;
}
if (CommandConverter.IsKnownType(command.OwnerType))
{
return true;
}
else
{
string localName = command.Name + "Command";
Type ownerType = command.OwnerType;
string typeName = ownerType.Name;
// Get them from Properties
PropertyInfo propertyInfo = ownerType.GetProperty(localName, BindingFlags.Public | BindingFlags.Static);
if (propertyInfo != null)
return true;
// Get them from Fields (ScrollViewer.PageDownCommand is a static readonly field
FieldInfo fieldInfo = ownerType.GetField(localName, BindingFlags.Static | BindingFlags.Public);
if (fieldInfo != null)
return true;
}
return false;
}
public override bool CanConvertFromString(string value, IValueSerializerContext context)
{
return true;
}
public override string ConvertToString(object value, IValueSerializerContext context)
{
if (value != null)
{
RoutedCommand command = value as RoutedCommand;
if (null != command && null != command.OwnerType)
{
// Known Commands, so write shorter version
if (CommandConverter.IsKnownType(command.OwnerType))
{
return command.Name;
}
else
{
ValueSerializer typeSerializer = null;
if (context == null)
{
throw new InvalidOperationException(SR.Get(SRID.ValueSerializerContextUnavailable, this.GetType().Name ));
}
// Get the ValueSerializer for the System.Type type
typeSerializer = context.GetValueSerializerFor(typeof(Type));
if (typeSerializer == null)
{
throw new InvalidOperationException(SR.Get(SRID.TypeValueSerializerUnavailable, this.GetType().Name ));
}
return typeSerializer.ConvertToString(command.OwnerType, context) + "." + command.Name + "Command";
}
}
}
else
return string.Empty;
throw GetConvertToException(value, typeof(string));
}
public override IEnumerable<Type> TypeReferences(object value, IValueSerializerContext context)
{
if (value != null)
{
RoutedCommand command = value as RoutedCommand;
if (command != null)
{
if (command.OwnerType != null && !CommandConverter.IsKnownType(command.OwnerType))
{
return new Type[] { command.OwnerType };
}
}
}
return base.TypeReferences(value, context);
}
public override object ConvertFromString(string value, IValueSerializerContext context)
{
if (value != null)
{
if (value != String.Empty)
{
Type declaringType = null;
String commandName;
// Check for "ns:Class.Command" syntax.
int dotIndex = value.IndexOf('.');
if (dotIndex >= 0)
{
// We have "ns:Class.Command" syntax.
// Find the type name in the form of "ns:Class".
string typeName = value.Substring(0, dotIndex);
if (context == null)
{
throw new InvalidOperationException(SR.Get(SRID.ValueSerializerContextUnavailable, this.GetType().Name ));
}
// Get the ValueSerializer for the System.Type type
ValueSerializer typeSerializer = context.GetValueSerializerFor(typeof(Type));
if (typeSerializer == null)
{
throw new InvalidOperationException(SR.Get(SRID.TypeValueSerializerUnavailable, this.GetType().Name ));
}
// Use the TypeValueSerializer to parse the "ns:Class" into a System.Type.
declaringType = typeSerializer.ConvertFromString(typeName, context) as Type;
// Strip out the "Command" part of "ns:Class.Command".
commandName = value.Substring(dotIndex + 1).Trim();
}
else
{
// Assume the known commands
commandName = value.Trim();
}
// Find the command given the declaring type & name (this is shared with CommandConverter)
ICommand command = CommandConverter.ConvertFromHelper( declaringType, commandName );
if (command != null)
{
return command;
}
}
else
{
return null; // String.Empty <==> null , (for roundtrip cases where Command property values are null)
}
}
return base.ConvertFromString(value, context);
}
}
}
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