Rails：如何转换<img src= >到 rails 应用程序中的 image_tag

Question

This is my first post here and it might sound awfully stupid. Im building my first rails app.

I have this line in my index.html.erb

    <img src="/assets/rand_front/<%= @random_image%>", style='height:50vw;width:100vw;margin-bottom:20px;' >

I want to use image_tag instead of the img src

What is the correct way to wrap it around the code?

So far I've tried <%= image_tag ( "/assets/rand_front/<%= @random_image%>", style='height:50vw;width:100vw;margin-bottom:20px;') %>

and <%= image_tag ( "/assets/rand_front/<%= @random_image%>"), style='height:50vw;width:100vw;margin-bottom:20px;' %> <%= image_tag ( "/assets/rand_front/<%= @random_image%>"), style='height:50vw;width:100vw;margin-bottom:20px;' %>

and many other versions, but none seems to work, what am I doing wrong? and how should I write it properly?

this <%= @random_image%> bit is taking this variable from the index method in the controller.

def index
   @products = Product.all.order(created_at: :desc).group_by(&:category_id)
    @images  = ["1.jpg", "2.jpg", "3.jpg", "4.jpg", "5.jpg", "6.jpg", "7.jpg", "8.jpg", "9.jpg", "10.jpg"]
    @random_no = rand(10)
    @random_image = @images[@random_no]
end

Answer 1

<%= image_tag "rand_front/#{@random_image}", style: 'height:50vw;width:100vw;margin-bottom:20px;' %>

image_tag will automatically add assets at start of the path

check Image Tag for Documentation

Answer 2

If I am not mistaken you have a rand_front folder in your assets folder so you should call image_tag("#{@random_image}") since by default the image_tag helper should check all the folders in the assets directory for the image name

For the CSS properties you can consider using the options hash which would allow you to pass in the CSS properties as keys with your desired values

image_tag("#{@random_image}", height: 20, width: 20) You can check out the documentation in the previous answer

Answer 3

This is what Ruby on Rails is explicitly processing

 <%= image_tag("source", {:style => "width:100px;"}) %>

(meaning that Ruby allows you to use this code with out the ( { } ),

For me, first starting out its important to know that this is how Ruby on Rails actually running the code.

In other words YES you could leave the ( { } ) formality out because Ruby will understand your code, hope that helps to clarify some...