判断浏览器版本 兼容ie8以以上，谷歌，火狐

//判断兼容性
function judgeCompatible(){
var brow = $.browser;
var bInfo = ""; //浏览器类型
//bInfo.version 版本
var version = brow.version.split(".")[0];
var userAgent = navigator.userAgent.toLocaleLowerCase(); //取得浏览器的userAgent字符串
if(brow.msie) {
bInfo = "IE"
}
if(brow.mozilla) {
bInfo = "Firefox"
}
if(brow.safari) {
bInfo = "safari"
}
if(brow.opera) {
bInfo = "opera"
}
if(brow.webkit) {
bInfo = "webkit"
}
if(brow.chrome) {
bInfo = "chrome";
var isEdge = userAgent.indexOf("windows nt 6.1; trident/7.0;") > -1 && !isIE; //判断是否IE的Edge浏览器
if(isEdge) {
bInfo = "Edge";
version = "";
}
}
//IE11特殊处理
var isIE11 = userAgent.indexOf('trident') > -1 && userAgent.indexOf("rv:11.0") > -1;
if(isIE11) {
bInfo = "IE"
}
var str = bInfo+","+version; //版本+版本号
return str;
}