ActiveRecord :: RecordNotFound - 提出哪個類？

Question

如果我在我的控制器下面的代碼：

def update 
    user = User.find(params[:user_id]) 
    house = House.find(params[:house_id]) 
rescue ActiveRecord::RecordNotFound 
    # How do I know whether finding user or finding house raised the exception? 
end 

我怎麼知道哪個find引發的異常？

Answer 1

在錯誤實例中似乎沒有任何方法來確定什麼引發了錯誤。

你可能做到這一點：

def update 
    user = User.find(params[:user_id]) 
    person = Person.find(params[:person_id]) 
    house = House.find(params[:house_id]) 
rescue ActiveRecord::RecordNotFound => e 
    case e.message 
    when /#{Person.name}/, /#{User.name}/ 
    do_something 
    when /#{House.name}/ 
    do_another_thing 
    end 
end 

或者，你可以使用find_by_id：

def update 
    user = User.find_by_id(params[:user_id]) 
    person = Person.find(params[:person_id]) 
    house = House.find_by_id(params[:house_id]) 

    do_something if user.nil? || person.nil? 
    do_something_else if house.nil? 
end