如何在Rails中自定义强参数

Question

i'm a rails newbie and I got a problem. When I user a strong parameter:

params.require(:project).permit(:project_name, :real_time)

I want to use it do update the project:

@project.update_attributes(user_project_params)

but before that, i want to change the value of

:real_time
ex: :realtime += 2

please tell me how can i do that?

Answer 1

Before calling user_project_params update the params

  params[:project][:real_time] += 2

Otherwise use callbacks

Answer 2

Any predefined modifications to the model objects are always done in model.

You can write a method in model and call it using callbacks

class Project< ActiveRecord::Base
  before_save :update_real_time

  private
    def update_real_time
      self.real_time= self.real_time +2
    end
end