node classes code example

Example 1: es6 class example

<script>
   class Student {
      constructor(rno,fname,lname){
         this.rno = rno
         this.fname = fname
         this.lname = lname
         console.log('inside constructor')
      }
      set rollno(newRollno){
         console.log("inside setter")
         this.rno = newRollno
      }
   }
   let s1 = new Student(101,'Sachin','Tendulkar')
   console.log(s1)
   //setter is called
   s1.rollno = 201
   console.log(s1)
</script>

Example 2: javascript class

class Rectangle {
  constructor(height, width) {
    this.height = height;
    this.width = width;
  }
  // Getter
  get area() {
    return this.calcArea();
  }
  // Method
  calcArea() {
    return this.height * this.width;
  }
}

const square = new Rectangle(10, 10);

console.log(square.area); // 100

Example 3: node js class

//Node js class: Here a quick code example

// Basic class
class Rectangle {
  
  // Constructor
  constructor(height, width) {
    // Member variables
    this.height = height;
    this.width = width;

    // Access static member variable
    Rectangle.count++;
  }
  
  // Getter
  get area() {
    return this.calcArea();
  }
  
  // Method
  calcArea() {
    return this.height * this.width;
  }

  // Static method
  static calcArea(width, height) {
    return width * height;
  }
}

// Static member variable
Rectangle.count = 0;


// Class instantiation
const square = new Rectangle(10, 10);

// Access member variable
console.log(square.height, square.width); // 10 10

// Call getter
console.log(square.area);	// 100

// Call method
console.log(square.calcArea()); // 100


// Access static member variable
console.log(Rectangle.count); // 1

// Call static method
console.log(Rectangle.calcArea(15, 15));  // 225

Example 4: class declaration in javascript

class NameOfClass {
//class declaration first letter should be capital it's a convention
  obj="text";
  obj2="some other text";
}
//always call class with "new" key word
console.log(new NameOfClass);