Section writers for appending to sections

public static void AppendSection(this IDictionary<string, RenderAsyncDelegate> args, string key, Func<dynamic, dynamic> text)
        {
            if (!args.ContainsKey(key))
            {
                args.Add(key, (async textWriter =>
                {                    
                    await text("").WriteAction(textWriter);                  
                }));
            }
            else {
                args[key] += (async textWriter =>
                 {
                     await text("").WriteAction(textWriter);                    
                 });
            }
        }

        public static void AppendSection(this IDictionary<string, RenderAsyncDelegate> args, string key, Task<IHtmlContent> contentTask)
        {
            if (!args.ContainsKey(key))
            {
                args.Add(key, (async textWriter =>
                {
                    var content = await contentTask;
                    content.WriteTo(textWriter, Microsoft.Extensions.WebEncoders.HtmlEncoder.Default);                                       
                }));
            }
            else {
                args[key] += (async textWriter =>
                {
                    var content = await contentTask;
                    content.WriteTo(textWriter, Microsoft.Extensions.WebEncoders.HtmlEncoder.Default);                   
                });
            }
        }  
Usage


this.SectionWriters.AppendSection("sectionName",@<script>
</script>
);

SectionWriters.AppendSection("sectionName", Html.PartialAsync("PartialViewName"));