如何不在我的模型中重複此代碼

Question

我在模型中有一段代碼，它根據運行該方法的當天時間設置開始日期和結束日期。

讓我們直接進入代碼示例：

#MODEL 
now = Time.now 
if now.hour >= 17 && now.hour <= 23 
    #night 
    n = now+1.day 
    startd = Time.local(now.year, now.month, now.day, 17, 00, 00) 
    endd = Time.local(n.year, n.month, n.day, 8, 00, 00) 
elsif now.hour >= 0 && now.hour <= 7 
    #morning 
    n = now-1.day 
    startd = Time.local(n.year, n.month, n.day, 8, 00, 00) 
    endd = Time.local(now.year, now.month, now.day, 17, 00, 00)  
end 

然後模型（相同或其他）裏面，我想運行一個發現裏面這個功能。

#MODEL(SAME OR OTHER) 
Model.find(:all, 
:conditions => ['created_at >= ? AND created_at <= ?', startd, endd]) 

的問題是，我要使用該功能來設置開始和結束日期的很多，我不知道在哪裏放置它不重複自己。它將用於不同的模型。

感謝您的任何幫助。

Answer 1

您可以將其包含在lib目錄中的模塊中。 RAILS_ROOT/lib中的所有ruby文件都會自動加載。

# time_calculations.rb 

module TimeCalculations 
    def calc_start_and_end_times 
    now = Time.now 
    if now.hour >= 17 && now.hour <= 23 
     #night 
     n = now+1.day 
     startd = Time.local(now.year, now.month, now.day, 17, 00, 00) 
     endd = Time.local(n.year, n.month, n.day, 8, 00, 00) 
    elsif now.hour >= 0 && now.hour <= 7 
     #morning 
     n = now-1.day 
     startd = Time.local(n.year, n.month, n.day, 8, 00, 00) 
     endd = Time.local(now.year, now.month, now.day, 17, 00, 00)  
    end 
    [startd, endd] 
    end 
end 

# model.rb 

class Model < ActiveRecord::Base 
    extend TimeCalculations 

    def self.my_find() 
    startd, endd = calc_start_and_end_times 
    Model.find(:all, 
     :conditions => ['created_at >= ? AND created_at <= ?', startd, endd]) 
    end 

end 

編輯，以反映最終的/正確的答案。

Answer 2

可以模型類裏面添加方法find_by_date_range（startd，endd），並使用Model.find_by_date_range（的東西，something_else）

Answer 3

最簡單的方法是將您的代碼添加到模塊，也許在一個初始化：

module SmartDates 

    def start_date 
    now = Time.now 
    if now.hour >= 17 && now.hour <= 23 
     #night 
     n = now+1.day 
     return Time.local(now.year, now.month, now.day, 17, 00, 00) 
    elsif now.hour >= 0 && now.hour <= 7 
     #morning 
     n = now-1.day 
     return Time.local(n.year, n.month, n.day, 8, 00, 00) 
    end 
    end 

    def end_date 
    now = Time.now 
    if now.hour >= 17 && now.hour <= 23 
     #night 
     n = now+1.day 
     return Time.local(n.year, n.month, n.day, 8, 00, 00) 
    elsif now.hour >= 0 && now.hour <= 7 
     #morning 
     n = now-1.day 
     return Time.local(now.year, now.month, now.day, 17, 00, 00) 
    end 
    end 

end 

# Now include your module 
ActiveRecord::Base.include(SmartDates) 
ActionController::Base.include(SmartDates) 

現在start_date和end_date在模型和控制器都可用。