51help TIY
码：
<html> <head> <script type="text/javascript"> function color(color) { document.forms[0].myInput.style.background=color } </script> </head> <body> <form> 消息：<br /> <input type="text" onkeydown="color('red')" onkeyup="color('blue')" name="myInput" size="20"> </form> </body> </html>
查看结果: