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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.
using System.ComponentModel;
using System.Globalization;
namespace System.Windows.Input
{
/// <summary>
/// Converter class for converting between a <see langword="string"/> and <see cref="MouseAction"/>.
/// </summary>
public class MouseActionConverter : TypeConverter
{
///<summary>
/// Used to check whether we can convert a <see langword="string"/> into a <see cref="MouseAction"/>.
///</summary>
///<param name="context">ITypeDescriptorContext</param>
///<param name="sourceType">type to convert from</param>
///<returns><see langword="true"/> if the given <paramref name="sourceType"/> can be converted from, <see langword="false"/> otherwise.</returns>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
// We can only handle string
return sourceType == typeof(string);
}
/// <summary>
/// Used to check whether we can convert specified value to <see langword="string"/>.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="destinationType">Type to convert to</param>
/// <returns><see langword="true"/> if conversion to <see langword="string"/> is possible, <see langword="false"/> otherwise.</returns>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
// We can convert to an InstanceDescriptor or to a string
if (destinationType != typeof(string))
return false;
// When invoked by the serialization engine we can convert to string only for known type
if (context is null || context.Instance is null)
return false;
// Make sure the value falls within defined set
return IsDefinedMouseAction((MouseAction)context.Instance);
}
/// <summary>
/// Converts <paramref name="source"/> of <see langword="string"/> type to its <see cref="MouseAction"/> represensation.
/// </summary>
/// <param name="context">Parser Context</param>
/// <param name="culture">Culture Info</param>
/// <param name="source">MouseAction String</param>
/// <returns>A <see cref="MouseAction"/> representing the <see langword="string"/> specified by <paramref name="source"/>.</returns>
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object source)
{
if (source is not string mouseAction)
throw GetConvertFromException(source);
ReadOnlySpan<char> mouseActionToken = mouseAction.AsSpan().Trim();
return mouseActionToken switch
{
_ when mouseActionToken.IsEmpty => MouseAction.None, // Special casing as produced by "ConvertTo"
_ when mouseActionToken.Equals("None", StringComparison.OrdinalIgnoreCase) => MouseAction.None,
_ when mouseActionToken.Equals("LeftClick", StringComparison.OrdinalIgnoreCase) => MouseAction.LeftClick,
_ when mouseActionToken.Equals("RightClick", StringComparison.OrdinalIgnoreCase) => MouseAction.RightClick,
_ when mouseActionToken.Equals("MiddleClick", StringComparison.OrdinalIgnoreCase) => MouseAction.MiddleClick,
_ when mouseActionToken.Equals("WheelClick", StringComparison.OrdinalIgnoreCase) => MouseAction.WheelClick,
_ when mouseActionToken.Equals("LeftDoubleClick", StringComparison.OrdinalIgnoreCase) => MouseAction.LeftDoubleClick,
_ when mouseActionToken.Equals("RightDoubleClick", StringComparison.OrdinalIgnoreCase) => MouseAction.RightDoubleClick,
_ when mouseActionToken.Equals("MiddleDoubleClick", StringComparison.OrdinalIgnoreCase) => MouseAction.MiddleDoubleClick,
_ => throw new NotSupportedException(SR.Format(SR.Unsupported_MouseAction, mouseActionToken.ToString()))
};
}
/// <summary>
/// Converts a <paramref name="value"/> of <see cref="MouseAction"/> to its <see langword="string"/> represensation.
/// </summary>
/// <param name="context">Serialization Context</param>
/// <param name="culture">Culture Info</param>
/// <param name="value">MouseAction value </param>
/// <param name="destinationType">Type to Convert</param>
/// <returns>A <see langword="string"/> representing the <see cref="MouseAction"/> specified by <paramref name="value"/>.</returns>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
if (value is null || destinationType != typeof(string))
throw GetConvertToException(value, destinationType);
return (MouseAction)value switch
{
MouseAction.None => string.Empty,
MouseAction.LeftClick => "LeftClick",
MouseAction.RightClick => "RightClick",
MouseAction.MiddleClick => "MiddleClick",
MouseAction.WheelClick => "WheelClick",
MouseAction.LeftDoubleClick => "LeftDoubleClick",
MouseAction.RightDoubleClick => "RightDoubleClick",
MouseAction.MiddleDoubleClick => "MiddleDoubleClick",
_ => throw new InvalidEnumArgumentException(nameof(value), (int)value, typeof(MouseAction))
};
}
/// <summary>
/// Helper function similar to <see cref="Enum.IsDefined{MouseAction}(MouseAction)"/>, just lighter and faster.
/// </summary>
/// <param name="mouseAction">The value to test against.</param>
/// <returns><see langword="true"/> if <paramref name="mouseAction"/> falls in enumeration range, <see langword="false"/> otherwise.</returns>
internal static bool IsDefinedMouseAction(MouseAction mouseAction)
{
return mouseAction >= MouseAction.None && mouseAction <= MouseAction.MiddleDoubleClick;
}
}
}
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