SOURCE

// $(function(){
//     // alert($("#LHWWangan").attr("href"));
//     // var LHWWangan,LHWWanganText;
//     // $LHWWangan = $("#LHWWangan").attr("href")+"xxx";
//     // $LHWWangan + "xxx";
//     // alert($LHWWangan);
//     // $LHWWanganText = $("#LHWWangan").text();
// //     alert($("#LHWWangan").text());
// });
// var LHWWanganText = document.getElementById("LHWWangan").text;
var LHWWanganNum = document.getElementById("LHWWangan").text.replace(/[^0-9]/ig,"");
var LHWWanganHerf = document.getElementById("LHWWangan").href="http://www.beian.gov.cn/portal/registerSystemInfo?recordcode=";


document.write(LHWWanganNum);

<a href="http://www.beian.gov.cn/" id="LHWWangan" target="_blank">鲁公网安备 37100402000471号</a>
<script>
//    documnet.getElementById("LHWWangan").href = "12313";
// documnet.getElementById("LHWWangan").href="http://www.beian.gov.cn/portal/registerSystemInfo?recordcode=123";
// document.getElementById("LHWWangan").innerHTML="123";
    // var x = document.getElementById("LHWWangan").href="http://www.beian.gov.cn/portal/registerSystemInfo?recordcode=123";
    // document.getElementById("LHWWangan").innerHTML = x;
</script>