Custom HtmlHelper Renders Text and not Markup

user_21318 0
Viewed 8144

I have written a basic HtmlHelper. Here's a test I wrote that simplifies what I was doing and to provide self assurance that it is happening when I use StringBuilder and TagBuilder objects:

public static string HelloWorld(this HtmlHelper htmlHelper, string name)
{
    var sb = new StringBuilder();
    var builder = new TagBuilder("span");
    builder.InnerHtml = "Hello, " + name + "!";
    sb.Append(builder.ToString(TagRenderMode.Normal));
    sb.Append("<br/>");

    return sb.ToString();
}

The output for this control encodes the string so I see the following: <span>Hello, Jason!</span><br/>

In my view, I'm using the following: @Html.HelloWorld("Jason")

Any ideas what I can be doing wrong?

asp.net-mvc-3 html-helper asp.net-mvc
4 Answers

Here is an answer for the year 2018 working with .Net Core 2

using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Mvc.Rendering;
using System.IO;

public static IHtmlContent HelloWorld(this IHtmlHelper html, string name)
{
    var span = new TagBuilder("span");
    span.InnerHtml.Append("Hello, " + name + "!");

    var br = new TagBuilder("br") {TagRenderMode = TagRenderMode.SelfClosing};

    string result;

    using (var writer = new StringWriter())
    {
        span.WriteTo(writer, System.Text.Encodings.Web.HtmlEncoder.Default);
        br.WriteTo(writer, System.Text.Encodings.Web.HtmlEncoder.Default);
        result = writer.ToString();
    }

    return new HtmlString(result);
}
user_75343410
Related