Html返回上一页面刷新

<script>    //返回上一页刷新        // var _msgb = $("#msg").val();                // alert(_msgb)                // if(_msgb == "3" || _msgb != ''){                    history.pushState(null, null, "{:U('index')}");                     window.onpopstate = function (event) {                            window.location.href="{:U('index')}";                     };                // }    </script>