搜索可能的多个参数

Question

我想通过可能的 2 个参数进行搜索，但也不需要两者都存在。现在，如果未选择任何内容，则 state_id 传递为“”，我不知道如何摆脱它。

查看：

<div dropdown-toggle>
 <%= form_tag('/municipalities', method: :get) do %>
 <%= select_tag(options_for_select(@dropdown), {:allow_blank => "Please select"}, class: "btn btn-default btn-lg dropdown-toggle")  %>
  <%= submit_tag "Search", class: "btn btn-default"
 %>
  <%= link_to "Reset", municipalities_path, class: "btn btn-default" %>
  <%= button_tag 'Counties Only', name: "municipality_type", value: "County", class: "btn btn-default pull-right" %>
 <% end %>
</div>

控制器（我还是新人，所以这还不够干净）

 def index

  @dropdown = State.all.map{ |s| [s.state, s.id]}
  @municipality = Municipality.order(:name)
  @count = @municipality.count

  if !params[:state_id].to_s.blank? && params[:municipality_type].present?
        @municipalities = Municipality.where(municipality_type: params[:municipality_type], state_id: params[:state_id])
        @forms = Form.where(municipality_id: @municipalities, state_id: @state)
        if !params[:state_id].blank?
          @present = params[:state_id] 
          @state = params[:state_id]
          @state_name = State.find(@state)
        end
        @count_state = @municipalities.count
  elsif params[:state_id].present?
    @present = params[:state_id] 
    @state = params[:state_id]
    @state_name = State.find(@state)
    @municipalities = Municipality.where(state_id: @state)
    @forms = Form.where(municipality_id: @municipalities)
    @count_state = @municipalities.count
  else
    @forms = nil
    @state = State.all
    @municipalities = Municipality.order(:name)
  end
end

Answer 1

如果我正确理解您的问题，您可以分别将您的条件简单地设置为if params[:state_id] && params[:municipality_type] 和elsif params[:state_id]，如果在表单中提交，它们将通过条件。

Answer 2

我会试一试，我可能没有正确理解您的意图。您似乎定义了很多不需要的变量。

我相信这就是让两个参数搜索城市所需的全部内容，但允许它们为空白：

def index
  @municipailies = Municipality.order(:name)
  state_id = params[:state_id]
  type = params[:municipality_type]
  @municipalities = Municipality.where(state_id: state_id) if state_id
  @municipalities = Municipality.where(municipality_type: type) if type
end