Ruby-on-rails 如何在 to_json 中获取回形针图像的 url
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How can I get url for paperclip image in to_json
提问by Giancarlo Corzo
I have a model that uses paperclip like this:
我有一个像这样使用回形针的模型：
has_attached_file :avatar, :styles => { :large => "100x100>" , :medium => "50x50>", :small => "20x20>" }, :default_url => '/images/missing-owner_:style.png'
I'm exporting this model with to_json method and I want to export the image url so I could use it in javascript.
我正在使用 to_json 方法导出此模型，并且我想导出图像 url，以便我可以在 javascript 中使用它。
I know I can access the url like this in the view:
我知道我可以在视图中访问这样的网址：
<%= image_tag model.avatar.url(:medium) %>
But How can I do the same in the to_json method.
但是我如何在 to_json 方法中做同样的事情。
I have some like this:
我有一些这样的：
respond_to do |format|
render :json => @model.to_json(:only => [:id,:name,:homephone,:cellphone])
end
回答by Ben Zittlau
I believe the easiest way for you to accomplish this will be to create a method in your object to return the avatar URL.
我相信您完成此操作的最简单方法是在您的对象中创建一个方法来返回头像 URL。
class Model < ActiveRecord::Base
...
def avatar_url
avatar.url(:medium)
end
...
end
This will then allow you to use the methods option when calling to_json with a simple method that does not require any parameters:
这将允许您在使用不需要任何参数的简单方法调用 to_json 时使用 methods 选项：
respond_to do |format|
render :json => @model.to_json(:only => [:id,:name,:homephone,:cellphone], :methods => [:avatar_url])
end
Which should yield you an output along these lines:
这应该会产生以下几行的输出：
{"id" => 1, "name" => "Cool model", "homephone" => 1234567890, "cellphone" => 0987654321, "avatar_url" => "www.coolsite.com/this_avatars_path"}
See these for reference:
请参阅这些以供参考：
Ruby to_json :methods arguments
回答by vinodh
show controller for display image json
用于显示图像 json 的显示控制器
localhost:3000/cities/1.json
本地主机：3000/城市/1.json
respond_to do |format|
format.html
format.json { render :json => @model.to_json(:methods => [:model_url]) }
end
