rails if else 检查失败然后救援

Question

我的控制器中有 2 种方法用于查找用户（注意 enabled_only 范围）：

before_filter :find_user, :only => :show
before_filter :find_any_user, :only => [:edit, :update, :destroy]

def find_user
  @user = User.enabled_only.find(params[:id])
rescue ActiveRecord::RecordNotFound
  flash[:alert] = "The user you were looking for could not be found"
  redirect_to root_path
end

def find_any_user
  @user = User.find(params[:id])
rescue ActiveRecord::RecordNotFound
  flash[:alert] = "The user you were looking for could not be found"
  redirect_to root_path
end

当然，这些可以合并为一种方法来检查:action == 'show' 是否存在，但我无法通过救援来捕获错误。我尝试了以下类似的方法，但没有成功：

before_filter :find_user, :only => [:show, :edit, :update, :destroy]

def find_user
  @user = if :action == 'show'
    User.enabled_only.find(params[:id])
  else
    User.find(params[:id])
  end
rescue ActiveRecord::RecordNotFound
  flash[:alert] = "The user you were looking for could not be found"
  redirect_to root_path
end

请告知如何做到这一点。

谢谢

Answer 1

您需要将要“保护”的代码封装在 begin 和 rescue 之间

before_filter :find_user, :only => [:show, :edit, :update, :destroy]

def find_user
  begin
    @user = if :action == 'show'
      User.enabled_only.find(params[:id])
    else
      User.find(params[:id])
    end
  rescue ActiveRecord::RecordNotFound
    flash[:alert] = "The user you were looking for could not be found"
    redirect_to root_path
  end
end

顺便说一句，您的测试:action == 'show' 永远不会是真的。 :action 是一个符号，其值为:action，它的值永远不会改变，'show' 也是如此，它的值永远不会改变。我不确定实现这一目标的最佳方法是什么，但你可以做到，但你可以做到if params[:action] == "show"