[RUBY] Rails linked_to tag

Introduction

I summarized how to write the link_to method of rails.

table of contents

1. What is the link_to method?
2. Basic writing

1. What is the link_to method?

The link_to method is the helper method used in the view. It is used when you want to display the link, and it generates the a tag of html. You can display the link by passing the character string to be displayed as a link and the link destination as arguments to the link_to method. Below, I will introduce how to write the basic source code of the link_to method.

2. Basic writing

--Link text as the first argument --Specify the path and URL in the second argument

You can create a link by passing these as arguments.

How to use URL or path

--When using URL

<%= link_to 'Yahoo', 'http://www.yahoo.co.jp/' %>

--When using a path

<%= link_to ‘User list’, ‘/users/index’ %>

How to use routing

If you want to create a link within the same application, use: Specify the route name set in "config / routes.rb" with "_path" added as the link destination. Use the following command to check the name of the routing. Run it in the application you created.

Terminal

rails routes

   Prefix        Verb       URI Pattern                  Controller#Action
   incomes       POST       /incomes(.:format)            incomes#create
   new_income    GET        /incomes/new(.:format)        incomes#new
   edit_income   GET        /incomes/:id/edit(.:format)   incomes#edit
   income        PATCH      /incomes/:id(.:format)        incomes#update
                 PUT        /incomes/:id(.:format)        incomes#update
                 DELETE     /incomes/:id(.:format)        incomes#destroy

For example, if you want to paste a link to the new action (new creation screen) of income_controller, write as follows.

--When using Prefix

<%= link_to 'Create New', new_income_path %>

--When using URI Pattern

<%= link_to 'Create New', ‘/incomes/new’ %>

When you need to specify the id

Some of the above URI patterns include id, which indicates ** which "income" to set the link to the edit screen **. By passing the id of income as an argument to "edit_income_path", the link destination will be set based on the id of the income data.

How to use the method option

HTTP method can be specified in the argument of link_to method. ** If nothing is specified, it will be GET **. The way to write is as follows.

<%= link_to ‘Delete’, income_path(params[:id]), method: :delete %>

You can also set the id attribute and class attribute.

How to use do ~ end

The link_to method can also be described using the do ~ end block as shown below.

<%= link_to income_path, class: 'hoge' do %>
　　<div>a</div>
      <h4>b</h4>
       <p>c</p>
<% end %>

Elements in link_to do ~ end can be linked at the same time.

Reference link

https://udemy.benesse.co.jp/development/web/link-to.html