GeezerVison

The World Wide Web, restored to 800 pixels of glory.

GeezerVison is showing javascript.info — Create new Calculator

back to the lesson

Create new Calculator

importance: 5

Create a constructor function Calculator that creates objects with 3 methods:

read() prompts for two values and saves them as object properties with names a and b respectively.
sum() returns the sum of these properties.
mul() returns the multiplication product of these properties.

For instance:

let calculator = new Calculator();
calculator.read();

alert( "Sum=" + calculator.sum() );
alert( "Mul=" + calculator.mul() );

Run the demo

Open a sandbox with tests.

function Calculator() {

  this.read = function() {
    this.a = +prompt('a?', 0);
    this.b = +prompt('b?', 0);
  };

  this.sum = function() {
    return this.a + this.b;
  };

  this.mul = function() {
    return this.a * this.b;
  };
}

let calculator = new Calculator();
calculator.read();

alert( "Sum=" + calculator.sum() );
alert( "Mul=" + calculator.mul() );

Open the solution with tests in a sandbox.

You are visitor 01402503 — GeezerVison does not store the pages you look up.
Best viewed with Netscape Navigator 4.7 or Internet Explorer 6 at 800×600. No cookies required.