判断网站是不是移动端访问，如果是自动跳转到手机网站

function mobile_device_detect(url) {
    var thisOS = navigator.platform;
    var os = new Array("iPhone", "iPod", "iPad", "android", "Nokia", "SymbianOS", "Symbian", "Windows Phone", "Phone", "Linux armv71", "MAUI", "UNTRUSTED/1.0", "Windows CE", "BlackBerry", "IEMobile");
    for (var i = 0; i < os.length; i++) {
        if (thisOS.match(os[i])) {
            window.location = url
        }
    }
    if (navigator.platform.indexOf('iPad') != -1) {
        window.location = url
    }
    var check = navigator.appVersion;
    if (check.match(/linux/i)) {
        if (check.match(/mobile/i) || check.match(/X11/i)) {
            window.location = url
        }
    }
    Array.prototype.in_array = function(e) {
        for (i = 0; i < this.length; i++) {
            if (this[i] == e) return true
        }
        return false
    }
}
mobile_device_detect("http://m.xxx.com");