第一步：把如下代码加入到<head>区域中
<SCRIPT LANGUAGE="JavaScript">
<!-- Begin
var text = "";
function getActiveText(e) {
text = (document.all) ? document.selection.createRange().text : document.getSelection();
document.theform.text.value = text;
return true;
}
document.onmouseup = getActiveText;
if (!document.all) document.captureEvents(Event.MOUSEUP);
