/// <summary>
/// 默认返回 Http404Handler 来处理没有任何匹配的IHttpHandler
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
protected virtual IHttpHandler CreateHandler404(HttpContext context)
{
return(new Http404Handler());
}
/// <summary>
/// 尝试根据路由规则来获取一个匹配的IHttpHandler实例，
/// 如果没有找到任何匹配，则返回 null
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
protected virtual IHttpHandler CreateHandlerByRouting(HttpContext context)
{
return(RoutingManager.Instance.CreateHandler(context));
}