IconConverter.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.ComponentModel;
using System.Globalization;
using System.IO;

namespace System.Drawing;

public class IconConverter : ExpandableObjectConverter
{
    public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
    {
        return sourceType == typeof(byte[]);
    }

    public override bool CanConvertTo(ITypeDescriptorContext? context, [NotNullWhen(true)] Type? destinationType)
    {
        return destinationType == typeof(byte[]) || destinationType == typeof(string)
            || destinationType == typeof(Image) || destinationType == typeof(Bitmap);
    }

    public override object? ConvertFrom(ITypeDescriptorContext? context, CultureInfo? culture, object value)
    {
        return value is byte[] bytes ? new Icon(new MemoryStream(bytes)) : base.ConvertFrom(context, culture, value);
    }

    public override object? ConvertTo(ITypeDescriptorContext? context, CultureInfo? culture, object? value, Type destinationType)
    {
        if (destinationType == typeof(string))
        {
            if (value is null)
            {
                return SR.none;
            }
            else if (value is Icon)
            {
                return value.ToString()!;
            }
        }
        else if (destinationType == typeof(byte[]))
        {
            if (value is Icon icon)
            {
                using MemoryStream ms = new();
                icon.Save(ms);
                return ms.ToArray();
            }
        }
        else if (destinationType == typeof(Image) || destinationType == typeof(Bitmap))
        {
            if (value is Icon icon)
            {
                return icon.ToBitmap();
            }
        }

        throw GetConvertFromException(value);
    }
}