Those parameters used to render as HTML attributes which is not very effective. For one, minlength is still not supported well by the browsers, so it wouldn't really work. Then, such things are better left to validation so a meaningful message can be shown to the user as to why their input is not being accepted. Thirdly, it is likely that they will be brought back through attribute splatting. Also, you can respond to events of the textbox and if input does not fit your needs, you can avoid updating it in the model, in case validation is not an option.