Determine if ASP.NET application is running locally

This worked for me with Application_Start

if (!HostingEnvironment.IsDevelopmentEnvironment)
{
      GlobalFilters.Filters.Add(new RequireHttpsAttribute());
}

To know more about how IsDevelopmentEnvironment is set, please look at the following thread.

In ASP.NET, what determines the value of HostingEnvironment.IsDevelopmentEnvironment?

See HttpRequest.IsLocal

bool isLocal = HttpContext.Current.Request.IsLocal;

You can check the Request.IsLocal property