Tag: js

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How to create a simple calculator program with javascript

This is a tutorial about how to create a simple calculator program with javascript, css, and html.

First create index.html file

<html>
<head>
    <title>Dice Simulator 2015</title>
    <link rel="stylesheet" href="style.css">
</head>  
<body>
  <h1>Calculator Example</h1>
  <p>Open the JavaScript developer console to interact.</p>
  <script src="calculator.js"></script>

</body>
</html>


Then create style.css file

* {
  font-family: Helvetica, Arial, sans-serif;
  text-align: center;
}


create calculator.js file

var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  },
  subtract: function(value) {
  this.sum = this.sum - value;
  },
  multiply: function(value) {
  this.sum = this.sum * value;
  },
  divide: function(value) {
  this.sum = this.sum / value;
  },
  clear: function() {
    this.sum = 0;
  }, 
  equals: function() {
    return this.sum;
  }
}


After open javascript console
Type in commands example
calculator.add(1)
calculator.add(1)
calculator.equals() // 3