add :photo to strong params for items add :avatar to strong params for user
<%= f.label "photo" %> <%= f.le_field :photo OR :avatar %>
already existing @user.avatar.attach(params[:avatar]) adding from file @user.avatar.attach(o: File.open(')) uploaded_io = params[:person][:picture]
def upload uploaded_file = params[:picture] File.open(Rails.root.join('public', 'uploads', uploaded_file.original_filename), 'wb') do |file| file.write(uploaded_file.read) end end
has many through <%= form_for post do |f| %>
<%= f.collection_check_boxes :category_ids, Category.all, :id, :name %> <%= f.submit %> <% end %> class PostsController < ApplicationController
...
private
def post_params params.require(:post).permit(:title, :content, category_ids:[]) end end
def create post = Post.create(post_params) redirect_to post end creates the post_categories in with it