ruby-on-rails - rails : How to know in advance if "save" is going to fail?

Question

考虑我的 Controller 的这段代码:

def create
  change_some_db_values
  buyer = Buyer.new(params[:buyer])
  if buyer.save
    redirect_to(:action => 'index')
  else
    render('new')
  end
end

如果 buyer.save我想提前知道会不会失败。如果它会失败，我不想执行 change_some_db_values .我怎么能做到这一点？

Answer 1

您可以 add a check for validity before saving :

def create
  buyer = Buyer.new(params[:buyer])
  if buyer.valid?
    change_some_db_values
  end
  if buyer.save
    redirect_to(:action => 'index')
  else
    render('new')
  end
end