代码如下，www.wendu.cc整理

<script>
var userAgent = navigator.userAgent.toLowerCase();
var is_opera = userAgent.indexOf(‘opera’) != -1 && opera.version();
var is_saf = userAgent.indexOf(‘applewebkit’) != -1 || navigator.vendor == ‘Apple Computer, Inc.’;
var is_webtv = userAgent.indexOf(‘webtv’) != -1;
var is_ie = (userAgent.indexOf(‘msie’) != -1 && !is_opera && !is_saf && !is_webtv) && userAgent.substr(userAgent.indexOf(‘msie’) + 5, 3);
function runCode(obj) {
         var winname = window.open(”, "_blank", ”);
         winname.document.open(‘text/html’, ‘replace’);
winname.opener = null; // 防止代码对论谈页面修改
         winname.document.write(obj.value);
         winname.document.close();
}
function saveCode(obj) {
         var winname = window.open(”, ‘_blank’, ‘top=10000’);
         winname.document.open(‘text/html’, ‘replace’);
         winname.document.write(obj.value);
         winname.document.execCommand(‘saveas’,”,’code.htm’);
         winname.close();
}
function copycode(obj) {
if(is_ie && obj.style.display != ‘none’) {
   var rng = document.body.createTextRange();
   rng.moveToElementText(obj);
   rng.scrollIntoView();
   rng.select();
   rng.execCommand("Copy");
   rng.collapse(false);
}
}
</script>
<textarea id=code cols=80 rows=15></textarea>  
<br />
<input type="button"onclick=runCode(code) value="运行代码" style="border:1px solid #B1B4CD;background:#696D81;color:#FFFFFF; padding-top:5px;"> <input type="button"onclick=copycode(code) style="border:1px solid #B1B4CD;background:#696D81;color:#FFFFFF; padding-top:5px;"value="复制代码" onclick="copycode(runcode3)"> <input type="button"onclick=saveCode(code) style="border:1px solid #B1B4CD;background:#696D81;color:#FFFFFF; padding-top:5px;"value="另存代码" onclick="saveCode(runcode3)"> 提示：您可以先修改部分代码再运行  
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