#ruby實現
  #接收微信伺服器資訊
  def process_request
    if check_signature?(params[:signature], params[:timestamp], params[:nonce]) #驗證訊息真實性
      if params[:xml][:MsgType] == "event"
        if params[:xml][:Event] == "subscribe"
          render "wechat/info", layout: false, :formats => :xml          #關注
        end
      else
        render "wechat/info", layout: false, :formats => :xml  #使用者輸入訊息時，回送歡迎關注
      end
    end
  end