MVC helper extension

Question

why do i get the error " Expected class, interface, enum or struct" with string underlined?

 public static string IsSelected(this HtmlHelper helper, string A, string B)

    {
         return "wtf";

    }

Answer 1

Your extension method needs to be inside a static class:

public static class MyExtensions
{
    public static string IsSelected( this HtmlHelper helper, string A, string B)
    {
        return "wtf";

    }
}