【text_input】
<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'>
window.onload=function(){
document.getElementById('my_button').onclick = function() {
document.getElementById('my_textbox').focus();
};
}
</script>
</head>
<body>
<input type="text" id="my_textbox" value="My Text" />
<button id="my_button">Focus</button>
</body>
</html>
