方法不是由控制器發現

Question

Rails 3.2 

在我的控制器/ tickets_controller.rb，我有：

def update 
    @ticket = Ticket.find(params[:id]) 
    @ticket.save_customer_info_if_present(params, @ticket) 
    respond_to do |format| 
    if @ticket.update_attributes(params[:lead_billing]) 
     format.html { redirect_to @ticket, notice: 'Ticket was successfully updated.' } 
     format.json { head :no_content } 
    else 
     format.html { render action: "edit" } 
     format.json { render json: @ticket.errors, status: :unprocessable_entity } 
    end 
    end 
end 

而且在我的模型/ ticket.rb，我有：

def self.save_customer_info_if_present(params, ticket) 
    customer_info_params = params[:customer_info] 
    if !customer_info_params.nil? 
    customer_info = CustomerInfo.new(
     :ticket_id => ticket.id, 
     :first => customer_info_params["first"], 
     :last => customer_info_params["last"], 
     :status => 'entered' 
    ) 
    customer_info.save 
    end 
end 

當更新動作運行時，我得到一個「找不到的方法：save_customer_info_if_present」

爲什麼不是控制器fin在模型中定義的自我方法？

Answer 1

你調用一個方法對模型的實例：

@ticket.save_customer_info_if_present(params, @ticket) 

但定義這個方法的類方法：

def self.save_customer_info_if_present(params, ticket) 
    # some code here 

從方法定義中刪除了self關鍵字，你也可以刪除票證參數，因爲您已經在票證實例上調用此方法（使其更易讀）：

def save_customer_info_if_present(params) 
    if params[:customer_info].present? 
    customer_info = CustomerInfo.new(
     :ticket_id => id, # just an id because it in the ticket instance 
     :first => params[:customer_info]["first"], 
     :last => params[:customer_info]["last"], 
     :status => 'entered' 
    ) 
    customer_info.save 
    end 
end 

當然

_{^{Class and Instance Methods in Ruby}}