//Copy to clipboard: ref http://forum.moztw.org/viewtopic.php?p=131407
function setCopy(txt) {
    var copied = false;
     if(window.clipboardData) {
        window.clipboardData.clearData();
        window.clipboardData.setData("Text", txt);
        copied = true;
     } else if (window.netscape) {
        try {
           netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
        } catch (e) {
           alert("被瀏覽器拒絕！\n請在瀏覽器網址列輸入'about:config'\n，將'signed.applets.codebase_principal_support'設為'true'");
        }
        var clip = Components.classes['@mozilla.org/widget/clipboard;1']
        .createInstance(Components.interfaces.nsIClipboard);
        if (!clip)
           return;
        var trans = Components.classes['@mozilla.org/widget/transferable;1']
        .createInstance(Components.interfaces.nsITransferable);
        if (!trans)
           return;
        trans.addDataFlavor('text/unicode');
        var str = new Object();
        var len = new Object();
        var str = Components.classes["@mozilla.org/supports-string;1"]
        .createInstance(Components.interfaces.nsISupportsString);
        var copytext = txt;
        str.data = copytext;
        trans.setTransferData("text/unicode",str,copytext.length*2);
        var clipid = Components.interfaces.nsIClipboard;
        if (!clip)
           return false;
        clip.setData(trans,null,clipid.kGlobalClipboard);
        copied = true;
     }
     if (copied) alert('已經把該文章引用網址複製到系統剪貼簿，您可以使用（Ctrl+V或滑鼠右鍵）貼上功能，通過其他軟體記錄或發送給您的朋友。');
     else alert("使用的瀏覽器不支援文字複製功能!");
}