Method: ActiveRecord::Persistence::ClassMethods#build

Defined in:

activerecord/lib/active_record/persistence.rb

#build(attributes = nil, &block) ⇒ Object

Builds an object (or multiple objects) and returns either the built object or a list of built objects.

The attributes parameter can be either a Hash or an Array of Hashes. These Hashes describe the attributes on the objects that are to be built.

Examples

# Build a single new object
User.build(first_name: 'Jamie')

# Build an Array of new objects
User.build([{ first_name: 'Jamie' }, { first_name: 'Jeremy' }])

# Build a single object and pass it into a block to set other attributes.
User.build(first_name: 'Jamie') do |u|
  u.is_admin = false
end

# Building an Array of new objects using a block, where the block is executed for each object:
User.build([{ first_name: 'Jamie' }, { first_name: 'Jeremy' }]) do |u|
  u.is_admin = false
end

# File 'activerecord/lib/active_record/persistence.rb', line 82

def build(attributes = nil, &block)
  if attributes.is_a?(Array)
    attributes.collect { |attr| build(attr, &block) }
  else
    new(attributes, &block)
  end
end