Add Link To The Current Page With Query Params as a Rails til

README.md

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 - [Ignore Poltergeist JavaScript Errors](rails/ignore-poltergeist-javascript-errors.md)
 - [Include Devise Helpers In Your Controller Tests](rails/include-devise-helpers-in-your-controller-tests.md)
 - [Inspect Previous Changes To ActiveRecord Object](rails/inspect-previous-changes-to-activerecord-object.md)
+- [Link To The Current Page With Query Params](rails/link-to-the-current-page-with-query-params.md)
 - [List All Installable Rails Versions](rails/list-all-installable-rails-versions.md)
 - [List The Enqueued Jobs](rails/list-the-enqueued-jobs.md)
 - [Load Records In Batches With find_each](rails/load-records-in-batches-with-find-each.md)

rails/link-to-the-current-page-with-query-params.md

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+# Link To The Current Page With Query Params
+
+The `link_to` method is an ActionView helper for generating an `a` tag within a
+Rails view. There are two arguments that tend to comprise this method: the link
+text and a path helper.
+
+```ruby
+<%= link_to 'Home', root_path %>
+```
+
+The `link_to` method can be used to generate a link to the current page with
+query params. You can do this be providing a hash instead of a path helper as
+the second argument.
+
+```ruby
+<%= link_to "All", {filter: 'all'} %>
+<%= link_to "New", {filter: 'new'} %>
+<%= link_to "Posted", {filter: 'posted'} %>
+```
+
+The hash can contain one or more key-value pairs which will be turned into
+query params and appended to the end of the current base path.
+
+If these are part of the `posts` index page, then they will render as:
+
+```html
+<a href="/posts?filter=all">All</a>
+<a href="/posts?filter=new">New</a>
+<a href="/posts?filter=posted">Posted</a>
+```
+
+This is a great way to create links for a Rails action that presents different
+data based on query params. Often this is an index page where filtering is
+needed.
+
+[source](https://gorails.com/episodes/rails-link-to-current-page-with-params)