<a asp-area="" asp-controller="Home" asp-action="Index" class="navbar-brand">taghelpersample</a>

@Html.ActionLink("taghelpersample", "Index", "Home",null, new { Class = "navbar-brand" })

<!--标签助手版form-->
<form asp-controller="Home" asp-action="Index" class="form-horizontal" method="post">

</form>
<!--Html帮助类版form-->
@using (Html.BeginForm("Index", "Home", FormMethod.Post,, new { Class = "form-horizontal" }))
{

}

 //类会默认转换为<text-collection></text-collection>
　　 public class TextCollectionTagHelper:TagHelper
 {
  public override void Process(TagHelperContext context, TagHelperOutput output)
  {
   base.Process(context, output);
  }
 }

public string Color { get; set; }

  public override void Process(TagHelperContext context, TagHelperOutput output)
  {
   output.TagName = "div";
   output.Attributes.Add("style", "color:" + Color);
   var text = "Hello,World";
   var h1 = new TagBuilder("h1");
   var h2 = new TagBuilder("h2");
   var h3 = new TagBuilder("h3");
   var h4 = new TagBuilder("h4");
   var h5 = new TagBuilder("h5");
   var h6 = new TagBuilder("h6");
   h1.InnerHtml.Append(text);
   h2.InnerHtml.Append(text);
   h3.InnerHtml.Append(text);
   h4.InnerHtml.Append(text);
   h5.InnerHtml.Append(text);
   h6.InnerHtml.Append(text);
   output.Content.AppendHtml(h1);
   output.Content.AppendHtml(h2);
   output.Content.AppendHtml(h3);
   output.Content.AppendHtml(h4);
   output.Content.AppendHtml(h5);
   output.Content.AppendHtml(h6);
  }

@addTagHelper *,taghelpersample

<text-collection color="red"></text-collection>
<text-collection color="blue"></text-collection>
<text-collection color="#666"></text-collection>