CODEWITHSUNDEEP
ruby-on-railsrubyruby-on-rails-3
tob88
tob88

Reputation: 2211

Looping through column_names with variable

I have a model method, which creates a report for a questionnaire app. Each column in the table represents a different question, and each row is an interviewee. It uses the column_names method to create an array of question ids, and then add the relevant responses.

def self.import_answers(params)

@members = Member.where(:questionnaire_id => params[:questionnaire])
@columns = Report.column_names
@members.each do |member|
  @report = Report.find_by_membership_number(member.membership_number)
  @responses = Response.where(:member_id => member.id)
  @columns.each do |column|
    question = column.to_s.gsub("q", "").to_i
    @response = @responses.where(:question_id => question).first
    unless @response.nil?
      @report.column = @response.response_id
      @report.save
    end
  end
end

end

This method breaks at the line @report.column.

I think it could be because the column_names method returns an array of strings, like so...

["q1", "q2", "q3", "q4", "q5", "q6", "q7", "q8", "q9", "q10"]

This means that the line @report.column iterates like 

@report."q1"

as opposed to...

@report.q1

which works.

I could be wrong about that! But either way, I am struggling to figure out how I can get it to work, any help would be much appreciated!

Upvotes: 0

Views: 241

Answers (3)

Harish Shetty
Harish Shetty

Reputation: 64373

You can use send("#{atr}=") to dynamically set an attribute. After reviewing your code you might be better off using update_attribute as it performs the set and save operations in one call.

I also noticed that you have the question id extraction logic outside the model. It might be better to encapsulate it in the Report model.

class Report < ActiveRecord::Base
  # extract the question id from the column
  def self.column_question_id(name)
    name[1..-1].to_i
  end
end

Now your code can be written as:

Report.column_names do |column|
  @response = @responses.find_by_question_id(Report.column_question_id(column))  
  @report.update_attribute(column, @response.response_id) if @response.present?
end

Upvotes: 1

Ahmish
Ahmish

Reputation: 1151

@report.send("#{column}=".to_sym, @response.response_id)

You can get more info here.

Upvotes: 0

vladdruzh
vladdruzh

Reputation: 208

@report.send(column.to_sym) = @response.response_id

Upvotes: 0

Related Questions