- Inheritance
Track unsaved attribute changes.
A newly instantiated object is unchanged:
person = Person.find_by_name('uncle bob')
person.changed? # => false
Change the name:
person.name = 'Bob' person.changed? # => true person.name_changed? # => true person.name_was # => 'uncle bob' person.name_change # => ['uncle bob', 'Bob'] person.name = 'Bill' person.name_change # => ['uncle bob', 'Bill']
Save the changes:
person.save person.changed? # => false person.name_changed? # => false
Assigning the same value leaves the attribute unchanged:
person.name = 'Bill' person.name_changed? # => false person.name_change # => nil
Which attributes have changed?
person.name = 'bob'
person.changed # => ['name']
person.changes # => { 'name' => ['Bill', 'bob'] }
Before modifying an attribute in-place:
person.name_will_change! person.name << 'by' person.name_change # => ['uncle bob', 'uncle bobby']
Classes & Modules
Constants
| Name | Description | |
|---|---|---|
| DIRTY_SUFFIXES | = ['_changed?', '_change', '_will_change!', '_was'] |
Methods
Class
| Visibility | Signature |
|---|---|
| public | included (base) |
Instance
| Visibility | Signature |
|---|---|
| public | changed () |
| public | changed? () |
| public | changes () |
Class Method Detail
included(base)
Instance Method Detail
changed()
List of attributes with unsaved changes.
person.changed # => [] person.name = 'bob' person.changed # => ['name']
changed?()
Do any attributes have unsaved changes?
person.changed? # => false person.name = 'bob' person.changed? # => true
changes()
Map of changed attrs => [original value, new value].
person.changes # => {}
person.name = 'bob'
person.changes # => { 'name' => ['bill', 'bob'] }