function isMobile()
{
        // 如果有HTTP_X_WAP_PROFILE则一定是移动设备
    if (isset ($_SERVER['HTTP_X_WAP_PROFILE']))
    return true;

    // 如果via信息含有wap则一定是移动设备,部分服务商会屏蔽该信息
    if (isset ($_SERVER['HTTP_VIA']))
    {
    // 找不到为flase,否则为true
    return stristr($_SERVER['HTTP_VIA'], "wap") ? true : false;
    }
    // 脑残法，判断手机发送的客户端标志,兼容性有待提高
    if (isset ($_SERVER['HTTP_USER_AGENT']))
    {
        $clientkeywords = array ('nokia','sony','ericsson','mot','samsung','htc','sgh','lg','sharp','sie-','philips','panasonic','alcatel','lenovo','iphone','ipod','blackberry','meizu','android','netfront','symbian','ucweb','windowsce','palm','operamini','operamobi','openwave','nexusone','cldc','midp','wap','mobile');
        // 从HTTP_USER_AGENT中查找手机浏览器的关键字
        if (preg_match("/(" . implode('|', $clientkeywords) . ")/i", strtolower($_SERVER['HTTP_USER_AGENT'])))
            return true;
    }
        // 协议法，因为有可能不准确，放到最后判断
    if (isset ($_SERVER['HTTP_ACCEPT']))
    {
    // 如果只支持wml并且不支持html那一定是移动设备
    // 如果支持wml和html但是wml在html之前则是移动设备
        if ((strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') !== false) && (strpos($_SERVER['HTTP_ACCEPT'], 'text/html') === false || (strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') < strpos($_SERVER['HTTP_ACCEPT'], 'text/html'))))
        {
            return true;
        }
    }
            return false;
}


/**
 * 判断是否为手机访问
 * @return  boolean
 */
function sp_is_mobile() {
    static $sp_is_mobile;

    if ( isset($sp_is_mobile) )
        return $sp_is_mobile;

    if ( empty($_SERVER['HTTP_USER_AGENT']) ) {
        $sp_is_mobile = false;
    } elseif ( strpos($_SERVER['HTTP_USER_AGENT'], 'Mobile') !== false // many mobile devices (all iPhone, iPad, etc.)
            || strpos($_SERVER['HTTP_USER_AGENT'], 'Android') !== false
            || strpos($_SERVER['HTTP_USER_AGENT'], 'Silk/') !== false
            || strpos($_SERVER['HTTP_USER_AGENT'], 'Kindle') !== false
            || strpos($_SERVER['HTTP_USER_AGENT'], 'BlackBerry') !== false
            || strpos($_SERVER['HTTP_USER_AGENT'], 'Opera Mini') !== false
            || strpos($_SERVER['HTTP_USER_AGENT'], 'Opera Mobi') !== false ) {
        $sp_is_mobile = true;
    } else {
        $sp_is_mobile = false;
    }

    return $sp_is_mobile;
}


function is_weixin() {
    if (strpos($_SERVER['HTTP_USER_AGENT'], 'MicroMessenger') !== false) {
        return true;
    } return false;
}

function is_qq() {
    if (strpos($_SERVER['HTTP_USER_AGENT'], 'QQ') !== false) {
        return true;
    } return false;
}

function is_alipay() {
    if (strpos($_SERVER['HTTP_USER_AGENT'], 'AlipayClient') !== false) {
        return true;
    } return false;
}



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