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<div class="section" id="working-with-entities">
<h1>Working With Entities<a class="headerlink" href="#working-with-entities" title="Permalink to this headline"></a></h1>
<p>CodeIgniter supports Entity classes as a first-class citizen in it&#8217;s database layer, while keeping
them completely optional to use. They are commonly used as part of the Repository pattern, but can
be used directly with the <a class="reference internal" href="model.html"><span class="doc">Model</span></a> if that fits your needs better.</p>
<div class="contents local topic" id="contents">
<ul class="simple">
<li><a class="reference internal" href="#entity-usage" id="id1">Entity Usage</a><ul>
<li><a class="reference internal" href="#create-the-entity-class" id="id2">Create the Entity Class</a></li>
<li><a class="reference internal" href="#create-the-model" id="id3">Create the Model</a></li>
<li><a class="reference internal" href="#working-with-the-entity-class" id="id4">Working With the Entity Class</a></li>
<li><a class="reference internal" href="#filling-properties-quickly" id="id5">Filling Properties Quickly</a></li>
</ul>
</li>
<li><a class="reference internal" href="#handling-business-logic" id="id6">Handling Business Logic</a></li>
<li><a class="reference internal" href="#data-mapping" id="id7">Data Mapping</a></li>
<li><a class="reference internal" href="#mutators" id="id8">Mutators</a><ul>
<li><a class="reference internal" href="#date-mutators" id="id9">Date Mutators</a></li>
<li><a class="reference internal" href="#property-casting" id="id10">Property Casting</a></li>
<li><a class="reference internal" href="#array-json-casting" id="id11">Array/Json Casting</a></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="entity-usage">
<h2><a class="toc-backref" href="#id1">Entity Usage</a><a class="headerlink" href="#entity-usage" title="Permalink to this headline"></a></h2>
<p>At its core, an Entity class is simply a class that represents a single database row. It has class properties
to represent the database columns, and provides any additional methods to implement the business logic for
that row. The core feature, though, is that it doesn&#8217;t know anything about how to persist itself. That&#8217;s the
responsibility of the model or the repository class. That way, if anything changes on how you need to save the
object, you don&#8217;t have to change how that object is used throughout the application. This makes it possible to
use JSON or XML files to store the objects during a rapid prototyping stage, and then easily switch to a
database when you&#8217;ve proven the concept works.</p>
<p>Let&#8217;s walk through a very simple User Entity and how we&#8217;d work with it to help make things clear.</p>
<p>Assume you have a database table named <code class="docutils literal"><span class="pre">users</span></code> that has the following schema:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nx">id</span> <span class="o">-</span> <span class="nx">integer</span>
<span class="nx">username</span> <span class="o">-</span> <span class="nx">string</span>
<span class="nx">email</span> <span class="o">-</span> <span class="nx">string</span>
<span class="nx">password</span> <span class="o">-</span> <span class="nx">string</span>
<span class="nx">created_at</span> <span class="o">-</span> <span class="nx">datetime</span>
</pre></div>
</div>
<div class="section" id="create-the-entity-class">
<h3><a class="toc-backref" href="#id2">Create the Entity Class</a><a class="headerlink" href="#create-the-entity-class" title="Permalink to this headline"></a></h3>
<p>Now create a new Entity class. Since there&#8217;s no default location to store these classes, and it doesn&#8217;t fit
in with the existing directory structure, create a new directory at <strong>app/Entities</strong>. Create the
Entity itself at <strong>app/Entities/User.php</strong>.</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$id</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$username</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$email</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$password</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$created_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$updated_at</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>At its simplest, this is all you need to do, though we&#8217;ll make it more useful in a minute. Note that all of the
database columns are represented in the Entity. This is required for the Model to populate the fields.</p>
</div>
<div class="section" id="create-the-model">
<h3><a class="toc-backref" href="#id3">Create the Model</a><a class="headerlink" href="#create-the-model" title="Permalink to this headline"></a></h3>
<p>Create the model first at <strong>app/Models/UserModel.php</strong> so that we can interact with it:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Models</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Model</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">UserModel</span> <span class="k">extends</span> <span class="nx">Model</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$table</span> <span class="o">=</span> <span class="s1">&#39;users&#39;</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$allowedFields</span> <span class="o">=</span> <span class="p">[</span>
<span class="s1">&#39;username&#39;</span><span class="p">,</span> <span class="s1">&#39;email&#39;</span><span class="p">,</span> <span class="s1">&#39;password&#39;</span>
<span class="p">];</span>
<span class="k">protected</span> <span class="nv">$returnType</span> <span class="o">=</span> <span class="s1">&#39;App\Entities\User&#39;</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$useTimestamps</span> <span class="o">=</span> <span class="k">true</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The model uses the <code class="docutils literal"><span class="pre">users</span></code> table in the database for all of its activities. We&#8217;ve set the <code class="docutils literal"><span class="pre">$allowedFields</span></code> property
to include all of the fields that we want outside classes to change. The <code class="docutils literal"><span class="pre">id</span></code>, <code class="docutils literal"><span class="pre">created_at</span></code>, and <code class="docutils literal"><span class="pre">updated_at</span></code> fields
are handled automatically by the class or the database, so we don&#8217;t want to change those. Finally, we&#8217;ve set our Entity
class as the <code class="docutils literal"><span class="pre">$returnType</span></code>. This ensures that all methods on the model that return rows from the database will return
instances of our User Entity class instead of an object or array like normal.</p>
</div>
<div class="section" id="working-with-the-entity-class">
<h3><a class="toc-backref" href="#id4">Working With the Entity Class</a><a class="headerlink" href="#working-with-the-entity-class" title="Permalink to this headline"></a></h3>
<p>Now that all of the pieces are in place, you would work with the Entity class as you would any other class:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$user</span> <span class="o">=</span> <span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">find</span><span class="p">(</span><span class="nv">$id</span><span class="p">);</span>
<span class="c1">// Display</span>
<span class="k">echo</span> <span class="nv">$user</span><span class="o">-&gt;</span><span class="na">username</span><span class="p">;</span>
<span class="k">echo</span> <span class="nv">$user</span><span class="o">-&gt;</span><span class="na">email</span><span class="p">;</span>
<span class="c1">// Updating</span>
<span class="nb">unset</span><span class="p">(</span><span class="nv">$user</span><span class="o">-&gt;</span><span class="na">username</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span> <span class="nb">isset</span><span class="p">(</span><span class="nv">$user</span><span class="o">-&gt;</span><span class="na">username</span><span class="p">)</span>
<span class="p">{</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">username</span> <span class="o">=</span> <span class="s1">&#39;something new&#39;</span><span class="p">;</span>
<span class="p">}</span>
<span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">save</span><span class="p">(</span><span class="nv">$user</span><span class="p">);</span>
<span class="c1">// Create</span>
<span class="nv">$user</span> <span class="o">=</span> <span class="k">new</span> <span class="nx">App\Entities\User</span><span class="p">();</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">username</span> <span class="o">=</span> <span class="s1">&#39;foo&#39;</span><span class="p">;</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">email</span> <span class="o">=</span> <span class="s1">&#39;foo@example.com&#39;</span><span class="p">;</span>
<span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">save</span><span class="p">(</span><span class="nv">$user</span><span class="p">);</span>
</pre></div>
</div>
<p>You may have noticed that the User class has all of the properties as <strong>protected</strong> not <strong>public</strong>, but you can still
access them as if they were public properties. The base class, <strong>CodeIgniterEntity</strong>, takes care of this for you, as
well as providing the ability to check the properties with <strong>isset()</strong>, or <strong>unset()</strong> the property.</p>
<p>When the User is passed to the model&#8217;s <strong>save()</strong> method, it automatically takes care of reading the protected properties
and saving any changes to columns listed in the model&#8217;s <strong>$allowedFields</strong> property. It also knows whether to create
a new row, or update an existing one.</p>
</div>
<div class="section" id="filling-properties-quickly">
<h3><a class="toc-backref" href="#id5">Filling Properties Quickly</a><a class="headerlink" href="#filling-properties-quickly" title="Permalink to this headline"></a></h3>
<p>The Entity class also provides a method, <code class="docutils literal"><span class="pre">fill()</span></code> that allows you to shove an array of key/value pairs into the class
and populate the class properties. Only properties that already exist in the class can be populated in this way.</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$data</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">request</span><span class="o">-&gt;</span><span class="na">getPost</span><span class="p">();</span>
<span class="nv">$user</span> <span class="o">=</span> <span class="k">new</span> <span class="nx">App\Entities\User</span><span class="p">();</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">fill</span><span class="p">(</span><span class="nv">$data</span><span class="p">);</span>
<span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">save</span><span class="p">(</span><span class="nv">$user</span><span class="p">);</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="handling-business-logic">
<h2><a class="toc-backref" href="#id6">Handling Business Logic</a><a class="headerlink" href="#handling-business-logic" title="Permalink to this headline"></a></h2>
<p>While the examples above are convenient, they don&#8217;t help enforce any business logic. The base Entity class implements
some smart <code class="docutils literal"><span class="pre">__get()</span></code> and <code class="docutils literal"><span class="pre">__set()</span></code> methods that will check for special methods and use those instead of using
the class properties directly, allowing you to enforce any business logic or data conversion that you need.</p>
<p>Here&#8217;s an updated User entity to provide some examples of how this could be used:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\I18n\Time</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$id</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$username</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$email</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$password</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$created_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$updated_at</span><span class="p">;</span>
<span class="k">public</span> <span class="k">function</span> <span class="nf">setPassword</span><span class="p">(</span><span class="nx">string</span> <span class="nv">$pass</span><span class="p">)</span>
<span class="p">{</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">password</span> <span class="o">=</span> <span class="nb">password_hash</span><span class="p">(</span><span class="nv">$pass</span><span class="p">,</span> <span class="nx">PASSWORD_BCRYPT</span><span class="p">);</span>
<span class="k">return</span> <span class="nv">$this</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">public</span> <span class="k">function</span> <span class="nf">setCreatedAt</span><span class="p">(</span><span class="nx">string</span> <span class="nv">$dateString</span><span class="p">)</span>
<span class="p">{</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">created_at</span> <span class="o">=</span> <span class="k">new</span> <span class="nx">Time</span><span class="p">(</span><span class="nv">$dateString</span><span class="p">,</span> <span class="s1">&#39;UTC&#39;</span><span class="p">);</span>
<span class="k">return</span> <span class="nv">$this</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">public</span> <span class="k">function</span> <span class="nf">getCreatedAt</span><span class="p">(</span><span class="nx">string</span> <span class="nv">$format</span> <span class="o">=</span> <span class="s1">&#39;Y-m-d H:i:s&#39;</span><span class="p">)</span>
<span class="p">{</span>
<span class="c1">// Convert to CodeIgniter\I18n\Time object</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">created_at</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">mutateDate</span><span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">created_at</span><span class="p">);</span>
<span class="nv">$timezone</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">timezone</span> <span class="o">??</span> <span class="nx">app_timezone</span><span class="p">();</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">created_at</span><span class="o">-&gt;</span><span class="na">setTimezone</span><span class="p">(</span><span class="nv">$timezone</span><span class="p">);</span>
<span class="k">return</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">created_at</span><span class="o">-&gt;</span><span class="na">format</span><span class="p">(</span><span class="nv">$format</span><span class="p">);</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The first thing to notice is the name of the methods we&#8217;ve added. For each one, the class expects the snake_case
column name to be converted into PascalCase, and prefixed with either <code class="docutils literal"><span class="pre">set</span></code> or <code class="docutils literal"><span class="pre">get</span></code>. These methods will then
be automatically called whenever you set or retrieve the class property using the direct syntax (i.e. $user-&gt;email).
The methods do not need to be public unless you want them accessed from other classes. For example, the <code class="docutils literal"><span class="pre">created_at</span></code>
class property will be accessed through the <code class="docutils literal"><span class="pre">setCreatedAt()</span></code> and <code class="docutils literal"><span class="pre">getCreatedAt()</span></code> methods.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">This only works when trying to access the properties from outside of the track. Any methods internal to the
class must call the <code class="docutils literal"><span class="pre">setX()</span></code> and <code class="docutils literal"><span class="pre">getX()</span></code> methods directly.</p>
</div>
<p>In the <code class="docutils literal"><span class="pre">setPassword()</span></code> method we ensure that the password is always hashed.</p>
<p>In <code class="docutils literal"><span class="pre">setCreatedAt()</span></code> we convert the string we receive from the model into a DateTime object, ensuring that our timezone
is UTC so we can easily convert the viewer&#8217;s current timezone. In <code class="docutils literal"><span class="pre">getCreatedAt()</span></code>, it converts the time to
a formatted string in the application&#8217;s current timezone.</p>
<p>While fairly simple, these examples show that using Entity classes can provide a very flexible way to enforce
business logic and create objects that are pleasant to use.</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="c1">// Auto-hash the password - both do the same thing</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">password</span> <span class="o">=</span> <span class="s1">&#39;my great password&#39;</span><span class="p">;</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">setPassword</span><span class="p">(</span><span class="s1">&#39;my great password&#39;</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="data-mapping">
<h2><a class="toc-backref" href="#id7">Data Mapping</a><a class="headerlink" href="#data-mapping" title="Permalink to this headline"></a></h2>
<p>At many points in your career, you will run into situations where the use of an application has changed and the
original column names in the database no longer make sense. Or you find that your coding style prefers camelCase
class properties, but your database schema required snake_case names. These situations can be easily handled
with the Entity class&#8217; data mapping features.</p>
<p>As an example, imagine you have the simplified User Entity that is used throughout your application:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$id</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$name</span><span class="p">;</span> <span class="c1">// Represents a username</span>
<span class="k">protected</span> <span class="nv">$email</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$password</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$created_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$updated_at</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Your boss comes to you and says that no one uses usernames anymore, so you&#8217;re switching to just use emails for login.
But they do want to personalize the application a bit, so they want you to change the name field to represent a user&#8217;s
full name now, not their username like it does currently. To keep things tidy and ensure things continue making sense
in the database you whip up a migration to rename the <cite>name</cite> field to <cite>full_name</cite> for clarity.</p>
<p>Ignoring how contrived this example is, we now have two choices on how to fix the User class. We could modify the class
property from <code class="docutils literal"><span class="pre">$name</span></code> to <code class="docutils literal"><span class="pre">$full_name</span></code>, but that would require changes throughout the application. Instead, we can
simply map the <code class="docutils literal"><span class="pre">full_name</span></code> column in the database to the <code class="docutils literal"><span class="pre">$name</span></code> property, and be done with the Entity changes:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$id</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$name</span><span class="p">;</span> <span class="c1">// Represents a full name now</span>
<span class="k">protected</span> <span class="nv">$email</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$password</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$created_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$updated_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$_options</span> <span class="o">=</span> <span class="p">[</span>
<span class="s1">&#39;datamap&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span>
<span class="s1">&#39;full_name&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;name&#39;</span>
<span class="p">],</span>
<span class="s1">&#39;dates&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span><span class="s1">&#39;created_at&#39;</span><span class="p">,</span> <span class="s1">&#39;updated_at&#39;</span><span class="p">,</span> <span class="s1">&#39;deleted_at&#39;</span><span class="p">],</span>
<span class="s1">&#39;casts&#39;</span> <span class="o">=&gt;</span> <span class="p">[]</span>
<span class="p">];</span>
<span class="p">}</span>
</pre></div>
</div>
<p>By adding our new database name to the <code class="docutils literal"><span class="pre">$datamap</span></code> array, we can tell the class what class property the database column
should be accessible through. The key of the array is the name of the column in the database, where the value in the array
is class property to map it to.</p>
<p>In this example, when the model sets the <code class="docutils literal"><span class="pre">full_name</span></code> field on the User class, it actually assigns that value to the
class&#8217; <code class="docutils literal"><span class="pre">$name</span></code> property, so it can be set and retrieved through <code class="docutils literal"><span class="pre">$user-&gt;name</span></code>. The value will still be accessible
through the original <code class="docutils literal"><span class="pre">$user-&gt;full_name</span></code>, also, as this is needed for the model to get the data back out and save it
to the database. However, <code class="docutils literal"><span class="pre">unset</span></code> and <code class="docutils literal"><span class="pre">isset</span></code> only work on the mapped property, <code class="docutils literal"><span class="pre">$name</span></code>, not on the original name,
<code class="docutils literal"><span class="pre">full_name</span></code>.</p>
</div>
<div class="section" id="mutators">
<h2><a class="toc-backref" href="#id8">Mutators</a><a class="headerlink" href="#mutators" title="Permalink to this headline"></a></h2>
<div class="section" id="date-mutators">
<h3><a class="toc-backref" href="#id9">Date Mutators</a><a class="headerlink" href="#date-mutators" title="Permalink to this headline"></a></h3>
<p>By default, the Entity class will convert fields named <cite>created_at</cite>, <cite>updated_at</cite>, or <cite>deleted_at</cite> into
<a class="reference internal" href="../libraries/time.html"><span class="doc">Time</span></a> instances whenever they are set or retrieved. The Time class provides a large number
of helpful methods in an immutable, localized way.</p>
<p>You can define which properties are automatically converted by adding the name to the <strong>options[&#8216;dates&#8217;]</strong> array:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$id</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$name</span><span class="p">;</span> <span class="c1">// Represents a full name now</span>
<span class="k">protected</span> <span class="nv">$email</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$password</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$created_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$updated_at</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$_options</span> <span class="o">=</span> <span class="p">[</span>
<span class="s1">&#39;dates&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span><span class="s1">&#39;created_at&#39;</span><span class="p">,</span> <span class="s1">&#39;updated_at&#39;</span><span class="p">,</span> <span class="s1">&#39;deleted_at&#39;</span><span class="p">],</span>
<span class="s1">&#39;casts&#39;</span> <span class="o">=&gt;</span> <span class="p">[],</span>
<span class="s1">&#39;datamap&#39;</span> <span class="o">=&gt;</span> <span class="p">[]</span>
<span class="p">];</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Now, when any of those properties are set, they will be converted to a Time instance, using the application&#8217;s
current timezone, as set in <strong>app/Config/App.php</strong>:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$user</span> <span class="o">=</span> <span class="k">new</span> <span class="nx">App\Entities\User</span><span class="p">();</span>
<span class="c1">// Converted to Time instance</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">created_at</span> <span class="o">=</span> <span class="s1">&#39;April 15, 2017 10:30:00&#39;</span><span class="p">;</span>
<span class="c1">// Can now use any Time methods:</span>
<span class="k">echo</span> <span class="nv">$user</span><span class="o">-&gt;</span><span class="na">created_at</span><span class="o">-&gt;</span><span class="na">humanize</span><span class="p">();</span>
<span class="k">echo</span> <span class="nv">$user</span><span class="o">-&gt;</span><span class="na">created_at</span><span class="o">-&gt;</span><span class="na">setTimezone</span><span class="p">(</span><span class="s1">&#39;Europe/London&#39;</span><span class="p">)</span><span class="o">-&gt;</span><span class="na">toDateString</span><span class="p">();</span>
</pre></div>
</div>
</div>
<div class="section" id="property-casting">
<h3><a class="toc-backref" href="#id10">Property Casting</a><a class="headerlink" href="#property-casting" title="Permalink to this headline"></a></h3>
<p>You can specify that properties in your Entity should be converted to common data types with the <strong>casts</strong> entry in
the <strong>$_options</strong> property. The <strong>casts</strong> option should be an array where the key is the name of the class property,
and the value is the data type it should be cast to. Casting only affects when values are read. No conversions happen
that affect the permanent value in either the entity or the database. Properties can be cast to any of the following
data types: <strong>integer</strong>, <strong>float</strong>, <strong>double</strong>, <strong>string</strong>, <strong>boolean</strong>, <strong>object</strong>, <strong>array</strong>, <strong>datetime</strong>, and
<strong>timestamp</strong>. Add question mark at the beginning of type to mark property as nullable, i.e. <strong>?string</strong>, <strong>?integer</strong>.</p>
<p>For example, if you had a User entity with an <strong>is_banned</strong> property, you can cast it as a boolean:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$is_banned</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$_options</span> <span class="o">=</span> <span class="p">[</span>
<span class="s1">&#39;casts&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span>
<span class="s1">&#39;is_banned&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;boolean&#39;</span><span class="p">,</span>
<span class="s1">&#39;is_banned_nullable&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;?boolean&#39;</span>
<span class="p">],</span>
<span class="s1">&#39;dates&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span><span class="s1">&#39;created_at&#39;</span><span class="p">,</span> <span class="s1">&#39;updated_at&#39;</span><span class="p">,</span> <span class="s1">&#39;deleted_at&#39;</span><span class="p">],</span>
<span class="s1">&#39;datamap&#39;</span> <span class="o">=&gt;</span> <span class="p">[]</span>
<span class="p">];</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="array-json-casting">
<h3><a class="toc-backref" href="#id11">Array/Json Casting</a><a class="headerlink" href="#array-json-casting" title="Permalink to this headline"></a></h3>
<p>Array/Json casting is especially useful with fields that store serialized arrays or json in them. When cast as:</p>
<ul class="simple">
<li>an <strong>array</strong>, they will automatically be unserialized,</li>
<li>a <strong>json</strong>, they will automatically be set as an value of json_decode($value, false),</li>
<li>a <strong>json-array</strong>, they will automatically be set as an value of json_decode($value, true),</li>
</ul>
<p>when you read the property&#8217;s value.
Unlike the rest of the data types that you can cast properties into, the:</p>
<ul class="simple">
<li><strong>array</strong> cast type will serialize,</li>
<li><strong>json</strong> and <strong>json-array</strong> cast will use json_encode function on</li>
</ul>
<p>the value whenever the property is set:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="k">namespace</span> <span class="nx">App\Entities</span><span class="p">;</span>
<span class="k">use</span> <span class="nx">CodeIgniter\Entity</span><span class="p">;</span>
<span class="k">class</span> <span class="nc">User</span> <span class="k">extends</span> <span class="nx">Entity</span>
<span class="p">{</span>
<span class="k">protected</span> <span class="nv">$options</span><span class="p">;</span>
<span class="k">protected</span> <span class="nv">$_options</span> <span class="o">=</span> <span class="p">[</span>
<span class="s1">&#39;casts&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span>
<span class="s1">&#39;options&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;array&#39;</span><span class="p">,</span>
<span class="s1">&#39;options_object&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;json&#39;</span><span class="p">,</span>
<span class="s1">&#39;options_array&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;json-array&#39;</span>
<span class="p">],</span>
<span class="s1">&#39;dates&#39;</span> <span class="o">=&gt;</span> <span class="p">[</span><span class="s1">&#39;created_at&#39;</span><span class="p">,</span> <span class="s1">&#39;updated_at&#39;</span><span class="p">,</span> <span class="s1">&#39;deleted_at&#39;</span><span class="p">],</span>
<span class="s1">&#39;datamap&#39;</span> <span class="o">=&gt;</span> <span class="p">[]</span>
<span class="p">];</span>
<span class="p">}</span>
<span class="nv">$user</span> <span class="o">=</span> <span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">find</span><span class="p">(</span><span class="mi">15</span><span class="p">);</span>
<span class="nv">$options</span> <span class="o">=</span> <span class="nv">$user</span><span class="o">-&gt;</span><span class="na">options</span><span class="p">;</span>
<span class="nv">$options</span><span class="p">[</span><span class="s1">&#39;foo&#39;</span><span class="p">]</span> <span class="o">=</span> <span class="s1">&#39;bar&#39;</span><span class="p">;</span>
<span class="nv">$user</span><span class="o">-&gt;</span><span class="na">options</span> <span class="o">=</span> <span class="nv">$options</span><span class="p">;</span>
<span class="nv">$userModel</span><span class="o">-&gt;</span><span class="na">save</span><span class="p">(</span><span class="nv">$user</span><span class="p">);</span>
</pre></div>
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