ASP.NET MVC razor: conditional attribute in HTML

Question

Code below doesn\'t seems clean. Any suggestion to improve the code?

class=\         


        

Answer 1

Based on defrosts answer here an adaptation, taking an object instead of a string:

    public static MvcHtmlString ConditionalAttr(this HtmlHelper helper, string attributeName, object value, Func condition)
    {
        if (string.IsNullOrEmpty(attributeName) || value == null)
        {
            return MvcHtmlString.Empty;
        }

        var render = condition != null ? condition() : true;

        return render ? 
            new MvcHtmlString($"{attributeName}=\"{HttpUtility.HtmlAttributeEncode(value.ToString())}\"") : 
            MvcHtmlString.Empty;
    }

This way you don't have to turn your other datatypes in strings before passing them, saving a fiew .ToString(). There is a difference tho: passing an empty string will still render. As example:

@Html.ConditionalAttr("data-foo", "", () => Model.IsFooNeeded)

// Ouput:
data-foo=""