判断是否微信客户端浏览器访问

$user_agent = $_SERVER['HTTP_USER_AGENT'];
if (strpos($user_agent, 'MicroMessenger') === false) {
    // 非微信浏览器禁止浏览
    echo "HTTP/1.1 401 Unauthorized";
} else {
    // 微信浏览器，允许访问
    echo "MicroMessenger";
    // 获取版本号
    preg_match('/.*?(MicroMessenger\/([0-9.]+))\s*/', $user_agent, $matches);
    echo '<br>Version:'.$matches[2];
}