循环遍历一个复选框数组列表，在控制器中的rails 3.1上的ruby中插入多条记录

Question

I have a list of check boxes created with check_box_tag ( <%= check_box_tag "user_ids[]", user.id %> ). Now i want to loop through all the check-boxes based on users_ids in controller and insert data of all the users selected.

Answer 1

As Meltemi says, the usual way to iterate in ruby is .each . In your case, probably something like this, in the controller that receives the form:

params[:user_ids].each do |user_id|
  u = User.find(user_id)
  u.do_something_to_that_user  #call a method or some such on the user
  something_else.users << u    #associate that user with something else
end

Alternatively, it can often be more efficient to do all of this in one go, though the exact form thereof depends on what you're doing with the user. For instance, if you want to associate the checked users with some record:

Record.user_ids = params[:user_ids]

Or if you want to update all of those users in some way:

User.where(:id => params[:user_id]).update_all(:attribute => some_value)