PALS3004: Web Programming Demo 5-2

<html>
<head>
<title>PALS3004: Web Programming Demo 5-2</title>
<script>
var total=0;
function button1click() {
  var value = parseFloat(document.getElementById("textbox1").value);
  total = total + value;
  var txt = document.getElementById("textarea1");
  txt.value = txt.value + "+ " + value + " = " + total + "\n";
  txt.scrollTop = txt.scrollHeight;   // position scroll position at bottom
}
</script>
<style>
#textarea1 { text-align:right; }
</style>
</head>
<body>
  <h2>Demo 5-2: Adding Machine</h2>
  <p><input type="text" id="textbox1" size="20" >
  <p><button onclick="button1click()">Add</button>
  <p><textarea id="textarea1" cols="20" rows="10">
  0
  </textarea>
</body>
</html>