nodejs classes code example
Example 1: javascript classes
//use classes by initiating one like so:
class MyClass {
constructor(FirstProperty, SecondProperty, etcetera) {
//The constructor function is called with the new class
//instance's parameters, so this will be called like so:
//var classExample = new MyClass("FirstProperty's Value", ...)
this.firstProperty = FirstProperty;
this.secondProperty = SecondProperty;
}
//creat methods just like functions:
method(Parameters) {
//Code Here
}
//getters are properties that are calculated when called, versus fixed
//variables, but still have no parenthesis when used
get getBothValues()
{
return [firstProperty, secondProperty];
}
}
//Note: this is all syntax sugar reducing the boilerplate versus a
// function-defined object.
Example 2: 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 3: es6 class example
class Polygon {
constructor(height, width) {
this.height = height;
this.width = width;
}
}
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);