Html.DescriptionFor() extension method for ASP.NET Core 3.1 and 5

HtmlExtensions.cs

// Copyright 2021 Ryan Crosby
// This code is licensed under the MIT license

using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.AspNetCore.Mvc.ViewFeatures;
using Microsoft.Extensions.DependencyInjection;
using System;
using System.Linq.Expressions;

namespace Gist
{
    public static class HtmlExtensions
    {
        public static IHtmlContent DescriptionFor<TModel, TValue>(this IHtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression)
        {
            if (html == null) throw new ArgumentNullException(nameof(html));
            if (expression == null) throw new ArgumentNullException(nameof(expression));


            var expressionProvider = html.ViewContext?.HttpContext?.RequestServices?.GetService<ModelExpressionProvider>()
                ?? new ModelExpressionProvider(html.MetadataProvider);
            var modelExpression = expressionProvider.CreateModelExpression(html.ViewData, expression);

            return new HtmlString(modelExpression.Metadata.Description);
        }
    }
}