constructor in dart code example

Example 1: dart this constructor

class MyClass {
  int param1;
  MyClass(this.param1);
}
final obj = MyClass(100);

class MyClassNamed {			// with named parameters
  int param1;
  MyClassNamed({required this.param1});
}
final objNamedParam = MyClassNamed(param1: 100);

Example 2: constructor in dart

//Creating object.
void main(){
  SelfDrivingCar myLamb = SelfDrivingCar('Floride');
  myLamb.drive();
 
}

//Initializing class Car.
class Car {
  int numberofwheels = 4;
  
  void drive() {
    print('this is a car');
  }
}

//using Inheritance 
class SelfDrivingCar extends Car {
  String destination='k';
  
  SelfDrivingCar(String userDestination){ //constructor
    destination = userDestination;
  }
  @override    //polymorphism.
  void drive() {
    super.drive();  // accessing parent's methods.
    
    print('sterring wheel to $destination');
    
  }
}

Example 3: dart call constructor in constructor

class Chipmunk {
  String name;
  int fame;

  Chipmunk.named(this.name, [this.fame]);

  Chipmunk.famous1() : this.named('Chip', 1000);
  factory Chipmunk.famous2() {
    var result = new Chipmunk.named('Chip');
    result.fame = 1000;
    return result;
  }
}

Example 4: constructor flutter

class Student{
  Student(int enNum){
    print(enNum);
  }
}

main(){
  var myStudent = new Student(15);
}

Example 5: dart constructor

void main() {
  Human jenny = Human(height1 :15);
    print(jenny.height);
  
  Human jerry = Human(height1: 20);
    print(jerry.height);
}

class Human {
  double height = 0;
  
  Human({height1 = 0}) { // constructor = initializes values of properties in the class.
    this.height = height1;
  }
  
}