如何使用ActiveStorage在rails中显示图像

gem 'activestorage'

require 'active_storage/engine'

rails active_storage:install:migrations
rails db:migrate

local:
  service: Disk
  root: <%= Rails.root.join("storage") %>

class User < ApplicationRecord
  has_one_attached :avatar
end

<!-- app/views/users/show.html.erb -->
<%= image_tag @user.avatar.variant(resize_to_limit: [100, 100]) if @user.avatar.attached? %>

<!-- app/views/users/edit.html.erb -->
<%= form_with model: @user, local: true do |form| %>
  <%= form.file_field :avatar %>
  <%= form.submit %>
<% end %>

# app/models/user.rb
class User < ApplicationRecord
  has_one_attached :avatar
end

# app/controllers/users_controller.rb
class UsersController < ApplicationController
  def show
    @user = User.find(params[:id])
  end

  def edit
    @user = User.find(params[:id])
  end

  def update
    @user = User.find(params[:id])
    if @user.update(user_params)
      redirect_to @user, notice: 'User was successfully updated.'
    else
      render :edit
    end
  end

  private

  def user_params
    params.require(:user).permit(:avatar)
  end
end

<!-- app/views/users/show.html.erb -->
<h1>User Profile</h1>
<%= image_tag @user.avatar.variant(resize_to_limit: [100, 100]) if @user.avatar.attached? %>

<!-- app/views/users/edit.html.erb -->
<h1>Edit User Profile</h1>
<%= form_with model: @user, local: true do |form| %>
  <%= form.file_field :avatar %>
  <%= form.submit %>
<% end %>