关于屏蔽backspace


<!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=gb2312" />
<title></title>
</head><body>
<table width="80%" border="1" align="center">
  <tr>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
  </tr>
  <tr>
    <td>&nbsp;</td>
    <td>
<input type="text" id="" name="" onkeydown="backSpace(false);"/>
</td>
    <td>&nbsp;</td>
  </tr>
  <tr>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
  </tr>
</table>
<script language="javascript" type="text/javascript">
document.onkeydown = function () {backSpace(true);}function backSpace(yesOrNo)
{
if(window.event.keyCode == 8 && yesOrNo)
{
window.event.keyCode = 0;
return false;
}
}
</script>
</body>
</html>