When is it appropriate to create HTML code in the controller (or back end)

Question

I am doing some complex logic involving loads of recursion to create a (complex) piece of HTML.

I started off doing this in the View using functions in Razor because I felt as HTML it belonged there.

But as it started getting more complex I thought I would rather do it in back-end code. Which it currently is.

It still feels a bit smellish though, and I am wondering if I should move it to the View again (which obviously clutters the view)

Which technically is more correct? When is it appropriate to use back-end code to generate HTML?

Thanks for your input.

Answer 1

Don't do it in controller. You can extend the HtmlHelper class and do the stuff there. For example if you are using a paging helper.

Create a static class HtmlHelpers

namespace YourMvcApplication.WebUI.HtmlHelpers
{
    public static class PagingHelpers
    {
        public static MvcHtmlString PageLinks(this HtmlHelper html,int totalPages)
        {
            StringBuilder result = new StringBuilder();
            // do the complex logic to create dynamic html and append to 
            // String Builder
            return MvcHtmlString.Create(result.ToString());
        }
    }
}

Add reference to this class in all views in web.config.

<namespaces>
    <add namespace="YourMvcApplication.WebUI.HtmlHelpers"/>
</namespaces>

Use and resuse this Html Helper methods wherever required.

<div>
    @Html.PageLinks(Model.TotalPages)
</div>