How to print out all key value pairs of an object

Say I have an object such as:

class Fruit{
   String? name;
   int? quantity;
   String? color;
}

Fruit exampleFruit = Fruit(name: 'Apple', quantity: 3, color: 'red');

What is the most efficient way for me to print out all the key-value pairs?

Pseudo Code I had in mind:

exampleFruit.keys.forEach((key){
   Text(key);
}

To clarify, the reason for this question is I have an object where some of the properties can be null. At the moment when displaying these properties, I was wondering if I can make this more efficient by mapping all the existing key-value pairs rather than checking for null and then displaying

Solution 1:

Well, you can create a toJson method inside your Fruit class, and always print out your parameters :

class Fruit {
  final String? name;
  final int? quantity;
  final String? color;

  const Fruit({
    this.color,
    this.name,
    this.quantity,
  });

  Map<String, dynamic> toJson() => {
       if(name != null) "name": name,
       if(quantity != null)  "quantity": quantity,
       if(color != null)  "color": color,
      };
}

And then :

  Fruit exampleFruit = Fruit(name: 'Apple', quantity: 3, color: 'red');
  print(exampleFruit.toJson()); // prints {name: Apple, quantity: 3, color: red}