Rails：如果check_box_tag中沒有選擇任何內容，則默認選擇

Question

我有一個應用程序，用戶可以將項目輸入數據庫。

有一個選項，他們可以爲他們的項目選擇許多不同的技術。目前，如果用戶沒有選擇至少1種技術，應用程序會標記錯誤。

我想改變這個，所以如果他們不選擇一項技術，它會自動下降爲「其他」。

這裏是我的項目負責人的行動，新的創造：

def new 
    @project = Project.new 
     @technol = Technol.new(params[:tech]) 

     @all_technols = Technol.order('tech ASC') 
     @all_technols = Technol.all 
     tech_ids = params[:technols][:id].reject(&:blank?) unless params[:technols].nil? 


     @project_technol = @project.projecttechnols.build 

    respond_to do |format| 
     format.html # new.html.erb 
     format.json { render json: @project } 
    end 
    end 



def create 
    @project = Project.new(params[:project]) 
     @project.client = params[:new_client] unless params[:new_client].blank? 
     @project.industry = params[:new_industry] unless params[:new_industry].blank? 
     @project.business_div = params[:new_business_div] unless params[:new_business_div].blank? 


if !params[:technols].nil? 

      params[:technols][:id].each do |tech| 


       if !tech.empty? 

        @project_technol = @project.projecttechnols.build(:technol_id => tech) 
        end 
      end 

end 

這裏是該技術領域

<ul> 


<% @all_technols.each do |technol| %> 



<li class="split"> 
<%= check_box_tag "project[technol_ids][]", technol.id, @project.technols.include?(technol) %> 
<%= technol.tech %> 
</li> 

<% end %> 
</ul> 

技術ID，在 「其它」 的新觀點技術表是「18」。那麼有沒有辦法說，如果沒有選擇技術，那麼:technol_id => ["18"]。

我得到的幫助較早，並建議我應該補充一點：

def create 
    ... 
    technol_ids = params[:technol_ids].blank? ? [18] : params[:technol_ids] 
    technol_ids.each do |id| 
    ... 
    end 
    ... 
end 

我無法得到這個工作。我認爲我沒有把它放在我的代碼中。我還是個新手，因此請在嘗試幫助時記住這一點。非常感謝

編輯

在沒有technols_id選擇

Processing by ProjectsController#create as HTML 
    Parameters: {"utf8"=>"Ô£ô", "authenticity_token"=>"8Hgc1GXqNhWkzO3Wgkfpf6z+fdImf6QvAv0XLbP0a5g=", "project"=>{"project 
_name"=>"Test", "archive"=>"0", "username"=>"test", "status"=>"Active", "exception_pm"=>"", "client"=>"", "business_d 
iv"=>"", "project_owner"=>"", "start_date"=>"11-12-2012", "first_name"=>"test", "last_name"=>"test", "fullname"=> 
"test test", "entry_date"=>"2012-11-26", "end_date"=>"19-12-2012", "techinfo"=>"Test", "role"=>"", "industry"=>"" 
, "summary"=>"Test", "lessons_learned"=>"Test", "customer_benefits"=>"Test", "financials"=>"£500,000 - £999,999 "}, "n 
ew_exception_pm"=>"Test", "new_client"=>"Test", "new_business_div"=>"Test", "new_project_owner"=>"Test", "new_role"=>"Te 
st", "new_industry"=>"Test", "commit"=>"Save New Project"} 

隨着1 technols_id

Started POST "/projects" for 192.168.16.127 at 2012-11-26 16:47:27 +0000 
Processing by ProjectsController#create as HTML 
    Parameters: {"utf8"=>"Ô£ô", "authenticity_token"=>"8Hgc1GXqNhWkzO3Wgkfpf6z+fdImf6QvAv0XLbP0a5g=", "project"=>{"project 
_name"=>"Test", "archive"=>"0", "username"=>"Test", "status"=>"Active", "exception_pm"=>"", "client"=>"", "business_d 
iv"=>"", "project_owner"=>"", "start_date"=>"11-12-2012", "first_name"=>"Test", "last_name"=>"McLaughlin", "fullname"=> 
"Test Test", "entry_date"=>"2012-11-26", "end_date"=>"20-12-2012", "technol_ids"=>["1"], "techinfo"=>"Test", "rol 
e"=>"", "industry"=>"", "summary"=>"Test", "lessons_learned"=>"Test", "customer_benefits"=>"Test", "financials"=>"£250, 
000 - £499,999 "}, "new_exception_pm"=>"Test", "new_client"=>"Test", "new_business_div"=>"Test", "new_project_owner"=>" 
Test", "new_role"=>"Test", "new_industry"=>"Test", "commit"=>"Save New Project"} 

Answer 1

首先，該字段的名稱應使用獲取參數，像我的例子一樣使用。 您正在收到一系列技術ID，對不對？因此，而不是使用，如果檢查零，使用此：

params[:project][:technol_ids] ||= [18] 

，如果它是零它會變成這個參數到數組。

params[:project][:technol_ids].each do |tech_id| 
    @project_technol = @project.projecttechnols.build(:technol_id => tech) 
end