associations

问题 I'm building two programs, a text editor and a zipper, but in this two programs I want to associate a file type to they, but how can I do this? Thanks. 回答1: You need to edit the registry: http://support.microsoft.com/kb/257592 You'll probably want to use regedit to see previous file associations, to make sure you don't mess up. c# registry basics 回答2: I know this is an old thread, but I don't think you should be messing around with the registry like that. Especially not since ClickOnce and

问题 I have a rails app with a has_many :through model like so: class Blog < ActiveRecord::Base has_many :blog_categorizations, dependent: :destroy has_many :categories, :through => :blog_categorizations accepts_nested_attributes_for :categories, allow_destroy: true end class Category < ActiveRecord::Base has_many :blog_categorizations, dependent: :destroy has_many :blog, :through => :blog_categorizations accepts_nested_attributes_for :blog, allow_destroy: true end class BlogCategorization <

问题 In my app I have the following models: Job and Worker. When a job is created, it is assigned a location attribute (Job#location) based on the address of the job. When workers fill out the site's application form, they should be able to indicate what locations they are interested in working in. Somehow I will be comparing a Worker's chosen locations with the location of a Job and sending notifications to Workers who have indicated that location, etc. In the form view, the possible locations

问题 My group model has_many posts, posts have_many comments. When I show the posts on a group, I want to order by the created at of the most recent comment, if there are any on a post, or by the created_at of the post itself. So an old post would jump back to the top of the list if it has a new comment. 回答1: I would stick to a little different approach: your Comment belongs_to :post and belongs_to accepts :touch option. Set it to true and your Post's updated_at will be automatically updated on a

问题 In my project, I have an Organization model and an Address model. Here is the association beetween the models: class Organization < ApplicationRecord has_one :address accepts_nested_attributes_for :address end class Address < ApplicationRecord belongs_to :organization end I added address attributes in my new organization form like this (form_with for Organization attributes and fields_for for Address attributes): <%= form_with(model: organization, local: true) do |form| %> <div class="field">

问题 i have a question about saving a new entity with an association which is a belongsToMany relation. Just a quick introduction. I have something like a settings table and a setting_values table. The user is connected to the settings by a joinTable called users_settings. So in summary: settings: id | name setting_values: id | setting_id | name | value | users_settings: id | user_id | setting_id | setting_value_id Now before the user is added I want to patch the entity of the user with all

问题 I cracked my head trying to realize how Symfony and Doctrine fetch associated entities. Lets imagine: i have several associated entities: Company (ManyToOne to City) City (ManyToOne to Region, OneToMany to Company) Region (ManyToOne to Country, OneToMany to City) Country (OneToMany to Region) When i render Company form i create Form Event Listener (on PRE_SET_DATA) that inserts Region and Country selectboxes to this form. The values in these fields must be set according to associated Region.

问题 Just getting started in rails and trying to refactor down a bit of my view, and I'm a bit stumped as to where to go for the answer since I'm inside an each loop I need access to the |item|. I'm pulling the writer from a CSV file, using a creator table and a HABTM assocation with books. The reason is sometimes the writer is also the illustrator and also the editor, I didn't want 3 (and more maybe) tables for each specific role of a book author. Books Model ( with CSV import ) writer = Creator

问题 I'm displaying my users in a table, and I am retrieving the company name and city with company_id users : id lastname firstname company_id role 1 doe john 2 author 2 deo jenne 2 admin 3 deus Joe 1 admin 4 Stewart Rob 1 author companies : id name city 1 New-York Company New-York 2 Paris Company Paris user display : <?php foreach($users as $user):?> <tr> <td><?= $user->lastname?></td> <td><?= $user->firstname?></td> <td><?= $user->companies->name ?></td> <td><?= $user->companies->city?></td>

问题 I'm having trouble with my Rails 4 app. I'm trying to follow this tutorial https://coderwall.com/p/rqjjca/creating-a-scoped-invitation-system-for-rails with some modifications. The tutorial skips over a few steps that are considered by the writer to be too easy to bother with - I think that's where I'm getting stuck. I have models for profile, project, team and user. The associations are: Profile.rb has_many :teams, foreign_key: "team_mate_id" has_many :team_projects, through: :teams, source: