Add default value on Insert

The following inserts a new product, no problem. Howeve, I have to prefix the filename with "\images\" so upon retrieval it will looki in the right directory.

How can I modify this code to append "\images\" to the filename column?

  def create
    @product = Product.new(@params[:product])
    if @product.save
      flash['notice'] = 'Product was successfully created.'
    end
  end

You can define a before_save callback in your model to call a function which
will prepend "\images\".

def create
     @product = Product.new(@params[:product])
     @product.filename = "\\images\\" + @product.filename
     if @product.save
       flash['notice'] = 'Product was successfully created.'
     end
   end

This approach might be problematic if you're creating new products in other
actions or elsewhere in your rails app. Using before_save won't pose the same
problem.