Rails如何使用除了id列表？

Question

Example I have some ids in my application controller:

@clicked = %w(32, 18, 13)

And in my controller I have:

@konkurrencer = Konkurrencer.find(:all, :order => 'created_at DESC').paginate(:page => params[:page], :per_page => 5)

How do I remove the Konkurrencer with the IDS 32, 18 and 13 from @konkurrencer?

And how to implement a clicked attribute (boolean) to konkurrencer. Example then it would be possible in the loop to do <% if kon.clicked %>CLICKED<% end %> it would be true if the kon had a id in the @clicked

Answer 1

You could use NOT IN, I've tested without the paginate part, try and let me now if it works:

@konkurrencer = Konkurrencer.where("id NOT IN(?)", @clicked).order("created_at DESC").paginate(:page => params[:page], :per_page => 5)

Be sure the @clicked variable is an array as moo is too short suggests.

Answer 2

你可以使用delete_if

Answer 3

As ghr mentioned, you could use delete_if but if you have a bunch of ids, the condition logic might get long. As an alternative, but somewhat expensive solution, you could just "subtract" the target items by building another collection:

 @konkurrencer = Konkurrencer.find(:all, :order => 'created_at DESC') - Konkurrencer.find(32,18,13)