我的一个模型中有一个这样的数据结构:
def image_size_limits
{
"web" => {"maxheight" => 480, "maxwidth" => 680, "minheight" => 400, "minwidth" => 600},
"phone" => {"height" => 345, "width" => 230, "minheight" => 300, "minwidth" => 200},
"tablet" => {"height" => 680, "width" => 480, "minheight" => 600, "minwidth" => 400},
"other" => {"height" => 680, "width" => 480, "minheight" => 600, "minwidth" => 400}
}
end
我在自定义验证器中使用此代码,我必须验证上传的图像的大小。我希望不仅可以在这个模型中使用这种数据结构,还可以在任何地方使用。在我所有的模型,视图和控制器中。
我将如何去做,我会放在哪里?
最佳答案
我会使用一个模块。
将其粘贴在您的lib
目录中。 (您可能需要配置Rails 3从lib
文件夹中自动加载类和模块。请参见this question。)
# lib/image_sizes.rb
module ImageSizes
def image_size_limits
{
"web" => {"maxheight" => 480, "maxwidth" => 680, "minheight" => 400, "minwidth" => 600},
"phone" => {"height" => 345, "width" => 230, "minheight" => 300, "minwidth" => 200},
"tablet" => {"height" => 680, "width" => 480, "minheight" => 600, "minwidth" => 400},
"other" => {"height" => 680, "width" => 480, "minheight" => 600, "minwidth" => 400}
}
end
end
然后在您的模型或控制器中:
class MyModel < ActiveRecord::Base
include ImageSizes
# ...
end
class MyController < ApplicationController
include ImageSizes
# ...
end
现在,每个包含
ImageSizes
模块的模型或控制器都可以访问该模块的方法,即image_size_limits
。