Question

我有三个模型，分别是经销商，城市和州，我在经销商和城市之间有一对多的关系。其次，城市与州之间存在一对多的关系：

class Dealer < ActiveRecord::Base
  belongs_to :city
end

class City < ActiveRecord::Base
  belongs_to :state
  has_many :dealers
end

class State < ActiveRecord::Base
  has_many :cities
end

在dealers_controller.rb中我有一个方法：

 def import
    Dealer.import(params[:file])
    redirect_to dealers_path, notice: "Products imported."
  end

这将参考经销商模型中的方法：

def self.import(file)
    spreadsheet = open_spreadsheet(file)
     city = City.new
     state = State.new
    header = spreadsheet.row(1)
    (2..spreadsheet.last_row).each do |i|
      row = Hash[[header, spreadsheet.row(i)].transpose]
      dealer = find_by_id(row["id"].to_i) || new
      dealer.dealerName = row["DEALERSHIPNAME"]
      dealer.address = row["ADDRESS"]
      dealer.pincode = row["PINCODE"]
      city.name = row["CITY"]
      state.name = row["STATE"]
      dealer.phoneNo = row["PHONENO"]
      dealer.mobileNo = row["MOBILE"]
      city.save!
      state.save!
      dealer.save!
    end
  end

  def self.open_spreadsheet(file)
    case File.extname(file.original_filename)
    when '.xls' then Roo::Excel.new(file.path)
    when '.xlsx' then Roo::Excelx.new(file.path)
    else raise "Unknown file type: #{file.original_filename}"
    end
  end

问题是经销商数据完全存储在经销商表中，但城市和州一直存储只有最后一条记录且经销商表中的city_id为空且city表中的state_id也为空。

如何使用此经销商模型在城市和州表中上传城市和州的全部数据？

我们如何上传excel文件，该文件将填充一对多关联中的所有三个表？

Answer 1

i was creating the city and states object once outside of the loop but its instance must be created for every row which is coming from excel sheet, stores states unique and stores city according to states  


  def self.import(file)
    spreadsheet = open_spreadsheet(file)

    header = spreadsheet.row(1)
    (2..spreadsheet.last_row).each do |i|
      row = Hash[[header, spreadsheet.row(i)].transpose]
      dealer = find_by_id(row["id"].to_i) || new
      dealer.dealerName = row["DEALERSHIPNAME"]
      dealer.address = row["ADDRESS"]
      dealer.pincode = row["PINCODE"]
      dealer.phoneNo = row["PHONENO"]
      dealer.mobileNo = row["MOBILE"]
      stateName = row["STATE"]
      state = State.where(:name=>stateName).first
      state_id = state.id unless state.nil?
      name = row["CITY"]
      city = City.where(:name=>name).first
      city_id = city.id unless city.nil?
      if state.nil?
        stateObj = State.new
        stateObj.name = stateName
        stateObj.save!
         if city.nil?
        cityObj = City.new
        cityObj.name = name
        cityObj.state_id = stateObj.id
        cityObj.save!
        dealer.city_id = cityObj.id
        dealer.save!
        else
        cityObj = City.new
        cityObj.name = city.name
        cityObj.state_id = stateObj.id
        cityObj.save!
        dealer.city_id = cityObj.id
        dealer.save!
        end
      else
        if city.nil?
        cityObj = City.new
        cityObj.name = name
        cityObj.state_id = state.id
        cityObj.save!
        dealer.city_id = cityObj.id
        dealer.save!
        else
        unless City.where(:name=>name).map{|c|c.state_id}.include? state.id
        cityObj = City.new
        cityObj.name = city.name
        cityObj.state_id = state.id
          cityObj.save!
        dealer.city_id = cityObj.id
        dealer.save!
        else
        dealer.city_id =  City.where(:name=>name,:state_id =>state.id).first.id
        dealer.save!
        end
        end
      end
  end
  end

  def self.open_spreadsheet(file)
    case File.extname(file.original_filename)
    when '.xls' then Roo::Excel.new(file.path)
    when '.xlsx' then Roo::Excelx.new(file.path)
    else raise "Unknown file type: #{file.original_filename}"
    end
    end

如何使用rails4

1 个答案: