ersatztv/ErsatzTV/Shared/MarkdownView.razor.cs

using System.Threading.Tasks;
using Ganss.XSS;
using Markdig;
using Microsoft.AspNetCore.Components;
using Microsoft.JSInterop;

namespace ErsatzTV.Shared
{
    public partial class MarkdownView
    {
        private string _content;

        [Inject]
        public IHtmlSanitizer HtmlSanitizer { get; set; }

        [Inject]
        public IJSRuntime JsRuntime { get; set; }

        [Parameter]
        public string Content
        {
            get => _content;
            set
            {
                _content = value;
                HtmlContent = ConvertStringToMarkupString(_content);
            }
        }

        public MarkupString HtmlContent { get; private set; }

        private MarkupString ConvertStringToMarkupString(string value)
        {
            if (!string.IsNullOrWhiteSpace(_content))
            {
                // Convert markdown string to HTML
                string html = Markdown.ToHtml(value, new MarkdownPipelineBuilder().UseAdvancedExtensions().Build());

                // Sanitize HTML before rendering
                string sanitizedHtml = HtmlSanitizer.Sanitize(html);

                // Return sanitized HTML as a MarkupString that Blazor can render
                return new MarkupString(sanitizedHtml);
            }

            return new MarkupString();
        }

        protected override async Task OnAfterRenderAsync(bool firstRender)
        {
            await JsRuntime.InvokeVoidAsync("styleMarkdown");
            await base.OnAfterRenderAsync(firstRender);
        }
    }
}