using Microsoft.Extensions.Configuration;

using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

using System.ComponentModel;

using System.Globalization;

​

​

var configuration = new ConfigurationBuilder()

    .AddInMemoryCollection(new Dictionary<string, string>()

    {

        { "Items:0", "Hello"},

        { "Items:1", "world"},

    })

    .Build();

​

try

{

    var options = configuration.Get<Options>();

    Console.WriteLine("Binding success.");

}

catch (Exception e)

{

    Console.WriteLine("Binding failure.");

}

​

​

class Options

{

    [TypeConverter(typeof(ItemCollectionConverter))]

    public ItemCollection Items { get; set; }

}

​

[TypeConverter(typeof(ItemCollectionConverter))]

class ItemCollection : ReadOnlyCollection<string>

{

    public ItemCollection(IList<string> list) : base(list)

    {

    }

}

​

class ItemCollectionConverter : TypeConverter

{

    public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)

    {

        return sourceType == typeof(IConfigurationSection);

    }

​

    public override object ConvertFrom(ITypeDescriptorContext? context, CultureInfo? culture, object value)

    {

        var items = new List<string>();

​

        foreach (var childSection in ((IConfigurationSection) value).GetChildren())

        {

            items.Add(childSection.Value!);

        }

​

        return new ItemCollection(items);

    }

}

​