JS复制粘贴另存代码

<SCRIPT> 
function Preview(obj) 
{ 
  var TestWin=open(''); 
  TestWin.document.write(obj.value); 
} 
function copyCode(obj) { 
    var rng = document.body.createTextRange(); 
    rng.moveToElementText(obj); 
    rng.scrollIntoView(); 
    rng.select(); 
    rng.execCommand("Copy"); 
    rng.collapse(false); 
} 
function saveCode(obj) { 
    var winname = window.open('', '_blank', 'top=10000'); 
    winname.document.open('text/html', 'replace'); 
    winname.document.writeln(obj.value); 
    winname.document.execCommand('saveas','','homepage.yesky.com.htm'); 
    winname.close(); 
} 
</SCRIPT>
<TEXTAREA id=code2 style="WIDTH: 400px; HEIGHT: 240px" rows=15 cols=47>
1
</TEXTAREA><BR><BUTTON onclick=Preview(code2)>运行代码</BUTTON><BUTTON onclick=copyCode(code2)>复制代码</BUTTON><BUTTON onclick=saveCode(code2)>另存代码</BUTTON>