<h2 id="heading-const-constructor">Const Constructor</h2>
<ul>
<li>Dart const constructor and how to use it to make all objects of a class constant at compile time.
</li>
<li>Immutability means being unable to be changed. If a value is immutable, that value cannot be changed.
</li>
<li>To make a field of a class immutable, you can use either the <code>const</code> or <code>final</code> keyword.
</li>
<li>If you use the <code>const</code> keyword, you need to initialize the value in the field declaration. Also, the value must be known at compile time.
</li>
<li><pre><code class="lang-dart"> final type fieldName;
</code></pre>
</li>
</ul>
<pre><code class="lang-dart">class Text {
 final String content;
 Text({this.content = ''});
}

void main() {
 const text = Text(content: 'Hello');
 print(text.content);
}
</code></pre>

## Const Constructor

* Dart const constructor and how to use it to make all objects of a class constant at compile time.
    
* Immutability means being unable to be changed. If a value is immutable, that value cannot be changed.
    
* To make a field of a class immutable, you can use either the `const` or `final` keyword.
    
* If you use the `const` keyword, you need to initialize the value in the field declaration. Also, the value must be known at compile time.
    
* ```dart
    final type fieldName;
    ```
    

```dart
class Text {
  final String content;
  Text({this.content = ''});
}

void main() {
  const text = Text(content: 'Hello');
  print(text.content);
}
```

Dart : Const Constructor

Const Constructor