js复制

function copyCode(testCode){
    //var testCode=document.getElementById(id).value;
    if(copy2Clipboard(testCode)!=false){
            alert("生成的代码已经复制到粘贴板，你可以使用Ctrl+V 贴到需要的地方去了哦！  ");
    }
}
copy2Clipboard=function(txt){
    if(window.clipboardData){
            window.clipboardData.clearData();
            window.clipboardData.setData("Text",txt);
    }
    else if(navigator.userAgent.indexOf("Opera")!=-1){
            window.location=txt;
    }
    else if(window.netscape){
            try{
                    netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
            }
            catch(e){
                    alert("您的firefox安全限制限制您进行剪贴板操作，请打开’about:config’将signed.applets.codebase_principal_support’设置为true’之后重试，相对路径为firefox根目录/greprefs/all.js");
                    return false;
            }
            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);
    }
}

支持IE firefox，不支持谷歌