Google AdSense Tag Helper for ASP.NET Core

Tag Helpers are a cool new feature in ASP.NET Core that let you define custom HTML elements that are processed server-side.

I thought that it would be neat to be able to emit Google AdSense ad code by writing a single HTML element:

<google-adsense ad-client="ca-pub-XXXXXXXXXXXXXXXX" ad-slot="XXXXXXXXXX" width="300" height="250" />

I was able to accomplish that with the following tag helper:

public class GoogleAdsenseTagHelper : TagHelper
{
    public string AdClient { get; set; }
    public string AdSlot { get; set; }
    public int Width { get; set; }
    public int Height { get; set; }

    public override void Process(TagHelperContext context, TagHelperOutput output)
    {
        output.SuppressOutput();

        if (!String.IsNullOrEmpty(AdClient) && !String.IsNullOrEmpty(AdSlot) && Width > 0 && Height > 0)
        {
            var sb = new StringBuilder();
            sb.AppendLine("<script async src=\"//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js\"></script>");
            sb.AppendLine("<ins class=\"adsbygoogle\"");
            sb.AppendLine($"     style=\"display:inline-block;width:{Width}px;height:{Height}px\"");
            sb.AppendLine($"     data-ad-client=\"{AdClient}\"");
            sb.AppendLine($"     data-ad-slot=\"{AdSlot}\"></ins>");
            sb.AppendLine("<script>");
            sb.AppendLine("(adsbygoogle = window.adsbygoogle || []).push({});");
            sb.AppendLine("</script>");

            output.Content.SetHtmlContent(sb.ToString());
        }
    }
}

I hope this blog post helps you out, or gives you inspiration for your own ASP.NET Core tag helpers.