51help TIY
码：
<html> <head> <script type="text/javascript"> function upperCase(x) { var y=document.getElementById(x).value document.getElementById(x).value=y.toUpperCase() } </script> </head> <body> Enter your name: <input type="text" id="fname" onkeyup="upperCase(this.id)"> </body> </html>
查看结果: