constructor in a class code example

Example 1: how to create a class with a constructor

class Car {

// fields  
  model: String;  
  doors: Number;  
  isElectric: Boolean;

constructor(model: String, doors: Number, isElectric: Boolean) {  
    this.model = model;  
    this.doors = doors;  
    this.isElectric = isElectric;  
  }

displayMake(): void {  
    console.log(`This car is ${this.model}`);  
  }

}

Example 2: classes and constructors

using namespace std;
 
class Line {
   public:
      void setLength( double len );
      double getLength( void );
      Line();  // This is the constructor
   private:
      double length;
};
 
// Member functions definitions including constructor
Line::Line(void) {
   cout << "Object is being created" << endl;
}
void Line::setLength( double len ) {
   length = len;
}
double Line::getLength( void ) {
   return length;
}

// Main function for the program
int main() {
   Line line;
 
   // set line length
   line.setLength(6.0); 
   cout << "Length of line : " << line.getLength() <<endl;
 
   return 0;
}