MVC 3 htmlhelper extension method to wrap around content

Question

I searched but could not find any quick solutions for an MVC 3 htmlhelper to create a wrapper method. What I\'m looking for is something like:

@html.createLi         


        

Answer 1

The way that this is done with BeginForm is that the return type MvcForm impliments IDisposable so that when used within a using statement, the Dispose method of MvcForm writes out the closing tag.

You can write an extension method that does exactly the same thing.

Here's one I just wrote to demonstrate.

First off, the extension method:

public static class ExtensionTest
{
    public static MvcAnchor BeginLink(this HtmlHelper htmlHelper)
    {
        var tagBuilder = new TagBuilder("a");
        htmlHelper.ViewContext.Writer
                        .Write(tagBuilder.ToString(
                                             TagRenderMode.StartTag));
        return new MvcAnchor(htmlHelper.ViewContext);
    }
}

And here's our new type, MvcAnchor:

public class MvcAnchor : IDisposable
{
    private readonly TextWriter _writer;
    public MvcAnchor(ViewContext viewContext)
    {
        _writer = viewContext.Writer;
    }

    public void Dispose()
    {
        this._writer.Write("");
    }
}

In your views you can now do:

@{
    using (Html.BeginLink())
    { 
        @Html.Raw("Hello World")
    }
}

Which yields the result:

Hello World

Expanding this slightly to deal with your exact requirement:

public static MvcAnchor BeginLink(this HtmlHelper htmlHelper, 
                                   string href, 
                                   string title)
{
    var tagBuilder = new TagBuilder("a");
    tagBuilder.Attributes.Add("href",href);
    tagBuilder.Attributes.Add("title", title);
    htmlHelper.ViewContext.Writer.Write(tagBuilder
                                    .ToString(TagRenderMode.StartTag));
    return new MvcAnchor(htmlHelper.ViewContext);
}

and our view:

@{
  using (Html.BeginLink("http://stackoverflow.com", "The Worlds Best Q&A site"))
  { 
      @Html.Raw("StackOverflow - Because we really do care")
  }
}

which yields the result:

   StackOverflow - Because we really do care