file_field

Returns a file upload input tag tailored for accessing a specified attribute (identified by method) on an object assigned to the template (identified by object). Additional options on the input tag can be passed as a hash with options. These options will be tagged onto the HTML as an HTML element attribute as in the example shown.

Using this method inside a form_with block will set the enclosing form’s encoding to multipart/form-data.

Options

• Creates standard HTML attributes for the tag.

• :disabled - If set to true, the user will not be able to use this input.

• :multiple - If set to true, *in most updated browsers* the user will be allowed to select multiple files.

• :include_hidden - When multiple: true and include_hidden: true, the field will be prefixed with an <input type="hidden"> field with an empty value to support submitting an empty collection of files. Since include_hidden will default to config.active_storage.multiple_file_field_include_hidden if you don’t specify include_hidden, you will need to pass include_hidden: false to prevent submitting an empty collection of files when passing multiple: true.

• :accept - If set to one or multiple mime-types, the user will be suggested a filter when choosing a file. You still need to set up model validations.

Examples

# Let's say that @user has avatar:
file_field(:avatar)
# => <input type="file" id="user_avatar" name="user[avatar]" />

# Let's say that @post has image:
file_field(:image, :multiple => true)
# => <input type="file" id="post_image" name="post[image][]" multiple="multiple" />

# Let's say that @post has attached:
file_field(:attached, accept: 'text/html')
# => <input accept="text/html" type="file" id="post_attached" name="post[attached]" />

# Let's say that @post has image:
file_field(:image, accept: 'image/png,image/gif,image/jpeg')
# => <input type="file" id="post_image" name="post[image]" accept="image/png,image/gif,image/jpeg" />

# Let's say that @attachment has file:
file_field(:file, class: 'file_input')
# => <input type="file" id="attachment_file" name="attachment[file]" class="file_input" />