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---
layout: default
title: Conditional rendering
parent: How-to guide
---
# Conditional rendering
Since 1.8.0
{: .label }
Components can implement a `#render?` method to be called after initialization to determine if the component should render.
Traditionally, the logic for whether to render a view could go in either the component template:
```erb
<% if user.requires_confirmation? %>
<div class="alert">Please confirm your email address.</div>
<% end %>
```
or the view that renders the component:
```erb
<% if current_user.requires_confirmation? %>
<%= render(ConfirmEmailComponent.new(user: current_user)) %>
<% end %>
```
Using the `#render?` hook simplifies the view:
```ruby
class ConfirmEmailComponent < ViewComponent::Base
erb_template <<-ERB
<div class="banner">
Please confirm your email address.
</div>
ERB
def initialize(user:)
@user = user
end
def render?
@user.requires_confirmation?
end
end
```
```erb
<%= render(ConfirmEmailComponent.new(user: current_user)) %>
```
_To assert whether a component has been rendered, use `assert_component_rendered` / `refute_component_rendered` from `ViewComponent::TestHelpers`._
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