mirror of
https://github.com/silverstripe/silverstripe-framework
synced 2024-09-16 06:26:27 +02:00
6888901468
* First cut * Temporarily disable composer.json for netlify build * POC * New recursive directory query, various refinements * Fix flexbox * new styled components plugin * Apply frontmatter delimiters * Mobile styles, animation * Search * Redesign, clean up * Nuke the cache, try again * fix file casing * Remove production env file * ID headers * Move app to new repo * Add frontmatter universally * Hide children changelogs * Add how to title * New callout tags * Revert inline code block change * Replace note callouts * Fix icons * Repalce images * Fix icon * Fix image links * Use proper SQL icon
87 lines
2.3 KiB
Markdown
87 lines
2.3 KiB
Markdown
---
|
|
title: Dynamic Default Fields
|
|
summary: Learn how to add default values to your models
|
|
---
|
|
|
|
# Default Values and Records
|
|
|
|
## Static Default Values
|
|
The [DataObject::$defaults](api:SilverStripe\ORM\DataObject::$defaults) array allows you to specify simple static values to be the default values when a record is created.
|
|
|
|
A simple example is if you have a dog and by default it's bark is "Woof":
|
|
```php
|
|
use SilverStripe\ORM\DataObject;
|
|
|
|
class Dog extends DataObject
|
|
{
|
|
private static $db = [
|
|
'Bark' => 'Varchar(10)',
|
|
];
|
|
|
|
private static $defaults = [
|
|
'Bark' => 'Woof',
|
|
];
|
|
}
|
|
```
|
|
|
|
## Dynamic Default Values
|
|
|
|
In many situations default values need to be dynamically calculated. In order to do this, the
|
|
[DataObject::populateDefaults()](api:SilverStripe\ORM\DataObject::populateDefaults()) method will need to be overloaded.
|
|
|
|
This method is called whenever a new record is instantiated, and you must be sure to call the method on the parent
|
|
object!
|
|
|
|
A simple example is to set a field to the current date and time:
|
|
|
|
```php
|
|
/**
|
|
* Sets the Date field to the current date.
|
|
*/
|
|
public function populateDefaults()
|
|
{
|
|
$this->Date = date('Y-m-d');
|
|
parent::populateDefaults();
|
|
}
|
|
```
|
|
|
|
It's also possible to get the data from any other source, or another object, just by using the usual data retrieval
|
|
methods. For example:
|
|
|
|
```php
|
|
/**
|
|
* This method combines the Title of the parent object with the Title of this
|
|
* object in the FullTitle field.
|
|
*/
|
|
public function populateDefaults()
|
|
{
|
|
if($parent = $this->Parent()) {
|
|
$this->FullTitle = $parent->Title . ': ' . $this->Title;
|
|
} else {
|
|
$this->FullTitle = $this->Title;
|
|
}
|
|
parent::populateDefaults();
|
|
}
|
|
```
|
|
|
|
## Static Default Records
|
|
The [DataObject::$default_records](api:SilverStripe\ORM\DataObject::$default_records) array allows you to specify default records created on dev/build.
|
|
|
|
A simple example of this is having a region model and wanting a list of regions created when the site is built:
|
|
```php
|
|
use SilverStripe\ORM\DataObject;
|
|
|
|
class Region extends DataObject
|
|
{
|
|
private static $db = [
|
|
'Title' => 'Varchar(45)',
|
|
];
|
|
|
|
private static $default_records = [
|
|
['Title' => 'Auckland'],
|
|
['Title' => 'Coromandel'],
|
|
['Title' => 'Waikato'],
|
|
];
|
|
}
|
|
```
|