function isBrowser() {
    var userAgent = navigator.userAgent;
    //微信内置浏览器
    if(userAgent.match(/MicroMessenger/i) == 'MicroMessenger') {
        return "MicroMessenger";
    }
    //QQ内置浏览器
    else if(userAgent.match(/QQ/i) == 'QQ') {
        return "QQ";
    }
    //Chrome
    else if(userAgent.match(/Chrome/i) == 'Chrome') {
        return "Chrome";
    }
    //Opera
    else if(userAgent.match(/Opera/i) == 'Opera') {
        return "Opera";
    }
    //Firefox
    else if(userAgent.match(/Firefox/i) == 'Firefox') {
        return "Firefox";
    }
    //Safari
    else if(userAgent.match(/Safari/i) == 'Safari') {
        return "Safari";
    }
    //IE
    else if(!!window.ActiveXObject || "ActiveXObject" in window) {
        return "IE";
    }
    else {
        return "未定义:"+userAgent;
    }
}