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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: MouseGestureConverter - Converts a MouseGesture string
// to the *Type* that the string represents
//
//
using System.ComponentModel; // for TypeConverter
using System.Globalization; // for CultureInfo
namespace System.Windows.Input
{
/// <summary>
/// MouseGesture - Converter class for converting between a string and the Type of a MouseGesture
/// </summary>
public class MouseGestureConverter : TypeConverter
{
private const char MODIFIERS_DELIMITER = '+' ;
///<summary>
/// CanConvertFrom()
///</summary>
///<param name="context">ITypeDescriptorContext</param>
///<param name="sourceType">type to convert from</param>
///<returns>true if the given type can be converted, false otherwise</returns>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
// We can only handle string.
if (sourceType == typeof(string))
{
return true;
}
else
{
return false;
}
}
/// <summary>
/// ConvertFrom
/// </summary>
/// <param name="context">Parser Context</param>
/// <param name="culture">Culture Info</param>
/// <param name="source">MouseGesture String</param>
/// <returns></returns>
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object source)
{
if (source is string && source != null)
{
string fullName = ((string)source).Trim();
string mouseActionToken;
string modifiersToken;
if (fullName.Length == 0)
return new MouseGesture(MouseAction.None, ModifierKeys.None);
// break apart LocalName and Prefix
int Offset = fullName.LastIndexOf(MODIFIERS_DELIMITER);
if (Offset >= 0)
{ // modifiers exists
modifiersToken = fullName.Substring(0,Offset);
mouseActionToken = fullName.Substring(Offset + 1);
}
else
{
modifiersToken = String.Empty;
mouseActionToken = fullName;
}
TypeConverter mouseActionConverter = TypeDescriptor.GetConverter(typeof(System.Windows.Input.MouseAction));
if (null != mouseActionConverter )
{
object mouseAction = mouseActionConverter.ConvertFrom(context, culture, mouseActionToken);
// mouseAction Converter will throw Exception, if it fails,
// so we don't need to check once more for bogus
// MouseAction values
if (mouseAction != null)
{
if (modifiersToken != String.Empty)
{
TypeConverter modifierKeysConverter = TypeDescriptor.GetConverter(typeof(System.Windows.Input.ModifierKeys));
if (null != modifierKeysConverter)
{
object modifierKeys = modifierKeysConverter.ConvertFrom(context, culture, modifiersToken);
if (modifierKeys != null && modifierKeys is ModifierKeys)
{
return new MouseGesture((MouseAction)mouseAction, (ModifierKeys)modifierKeys);
}
}
}
else
{
return new MouseGesture((MouseAction)mouseAction);
}
}
}
}
throw GetConvertFromException(source);
}
///<summary>
///TypeConverter method override.
///</summary>
///<param name="context">ITypeDescriptorContext</param>
///<param name="destinationType">Type to convert to</param>
///<returns>true if conversion is possible</returns>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
// We can convert to an InstanceDescriptor or to a string.
if (destinationType == typeof(string))
{
// When invoked by the serialization engine we can convert to string only for known type
if (context != null && context.Instance != null)
{
MouseGesture mouseGesture = context.Instance as MouseGesture;
if (mouseGesture != null)
{
return (ModifierKeysConverter.IsDefinedModifierKeys(mouseGesture.Modifiers)
&& MouseActionConverter.IsDefinedMouseAction(mouseGesture.MouseAction));
}
}
}
return false;
}
/// <summary>
/// ConvertTo()
/// </summary>
/// <param name="context">Serialization Context</param>
/// <param name="culture">Culture Info</param>
/// <param name="value">MouseGesture value </param>
/// <param name="destinationType">Type to Convert</param>
/// <returns>string if parameter is a MouseGesture</returns>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
if (destinationType == typeof(string))
{
if (value == null)
return String.Empty;
MouseGesture mouseGesture = value as MouseGesture;
if (mouseGesture != null)
{
string strGesture = "";
TypeConverter modifierKeysConverter = TypeDescriptor.GetConverter(typeof(System.Windows.Input.ModifierKeys));
if (null != modifierKeysConverter)
{
strGesture += modifierKeysConverter.ConvertTo(context, culture, mouseGesture.Modifiers, destinationType) as string;
if (strGesture != String.Empty)
{
strGesture += MODIFIERS_DELIMITER ;
}
}
TypeConverter mouseActionConverter = TypeDescriptor.GetConverter(typeof(System.Windows.Input.MouseAction));
if (null != mouseActionConverter)
{
strGesture += mouseActionConverter.ConvertTo(context, culture, mouseGesture.MouseAction, destinationType) as string;
}
return strGesture;
}
}
throw GetConvertToException(value,destinationType);
}
}
}
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