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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
//
// Description: class for input scope type-converter
//
// Please refer to the design specfication http://avalon/Cicero/Specifications/Stylable%20InputScope.mht
//
//
using System;
using System.Collections.Generic;
using System.Windows.Input;
using System.ComponentModel;
using System.Globalization;
using System.ComponentModel.Design.Serialization;
namespace System.Windows.Input
{
///<summary>
/// type-converter which performs type conversions for inputscope
///</summary>
/// <speclink>http://avalon/Cicero/Specifications/Stylable%20InputScope.mht</speclink>
public class InputScopeConverter : TypeConverter
{
///<summary>
/// Returns whether this converter can convert an object of one type to InputScope type
/// InputScopeConverter only supports string type to convert from
///</summary>
///<param name="context">
/// The conversion context.
///</param>
///<param name="sourceType">
/// The type to convert from.
///</param>
///<returns>
/// True if conversion is possible, false otherwise.
///</returns>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
// We can only handle string.
if (sourceType == typeof(string))
{
return true;
}
return false;
}
///<summary>
/// Returns whether this converter can convert the object to the specified type.
/// InputScopeConverter only supports string type to convert to
///</summary>
///<param name="context">
/// The conversion context.
///</param>
///<param name="destinationType">
/// The type to convert to.
///</param>
///<returns>
/// True if conversion is possible, false otherwise.
///</returns>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
#if false
if (typeof(string) == destinationType)
{
if (null == context)
{
return true;
}
if (null != context.Instance && context.Instance is DependencyObject)
{
InputScope inputscope = (InputScope)((DependencyObject)context.Instance).GetValue(InputMethod.InputScopeProperty);
if (inputscope != null && inputscope.Names.Count == 1)
{
return true;
}
}
}
#endif
return false;
}
///<summary>
/// Converts the given value to InputScope type
///</summary>
/// <param name="context">
/// The conversion context.
/// </param>
/// <param name="culture">
/// The current culture that applies to the conversion.
/// </param>
/// <param name="source">
/// The source object to convert from.
/// </param>
/// <returns>
/// InputScope object with a specified scope name, otherwise InputScope with Default scope.
/// </returns>
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object source)
{
string stringSource = source as string;
InputScopeNameValue sn = InputScopeNameValue.Default;
InputScope inputScope;
if (null != stringSource)
{
ReadOnlySpan<char> spanSource = stringSource;
spanSource = spanSource.Trim();
int periodPos = spanSource.LastIndexOf('.');
if (periodPos != -1)
{
spanSource = spanSource.Slice(periodPos + 1);
}
if (!spanSource.IsEmpty)
{
sn = Enum.Parse<InputScopeNameValue>(spanSource);
}
}
inputScope = new InputScope();
inputScope.Names.Add(new InputScopeName(sn));
return inputScope;
}
#if true
///<summary>
/// Converts the given value as InputScope object to the specified type.
/// This converter only supports string type as a type to convert to.
///</summary>
/// <param name="context">
/// The conversion context.
/// </param>
/// <param name="culture">
/// The current culture that applies to the conversion.
/// </param>
/// <param name="value">
/// The value to convert.
/// </param>
/// <param name="destinationType">
/// The type to convert to.
/// </param>
/// <returns>
/// A new object of the specified type (string) converted from the given InputScope object.
/// </returns>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
InputScope inputScope = value as InputScope;
if (null != destinationType && null != inputScope)
{
if (destinationType == typeof(string))
{
return Enum.GetName(((InputScopeName)inputScope.Names[0]).NameValue);
}
}
return base.ConvertTo(context, culture, value, destinationType);
}
#endif
}
}
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