function detectBrowser()

    {

        var browser = navigator.appName

        if(navigator.userAgent.indexOf("MSIE")>0){ 

            var b_version = navigator.appVersion

            var version = b_version.split(";");

            var trim_Version = version[1].replace(/[ ]/g,"");

            if ((browser=="Netscape"||browser=="Microsoft Internet Explorer"))

            {

                if(trim_Version == 'MSIE8.0' || trim_Version == 'MSIE7.0' || trim_Version == 'MSIE6.0'){

                    alert('请使用IE9.0版本以上进行访问');

                    return;

                }

            }

        }

   }

    detectBrowser();