<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>1</title>
<script>
function adda(){
document.getElementById('texta').value++;
}
function addb(){
document.getElementById('textb').value++;
}
</script>
</head>
<body>
<textarea id="texta">1</textarea><input type="button" onclick="adda()" value="Add 1"/><br/><br/>
<input type="text" id="textb" value="1"/><input type="button" onclick="addb()" value="Add 1"/>
</body>
</html>
