php curl检查远程图片是否有效

    function Check($url){
        $ch = curl_init();
        $timeout = 10;
        curl_setopt ($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_HEADER, 1);//将文件的信息作为数据流输出
        curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);//将获取的信息以字符串返回
        curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);//设置等待时间
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER , false);//禁止验证对等证书
        $contents = curl_exec($ch);
        //echo $contents;
//
//        if (preg_match("/404/", $contents)){
//            return false;
//        }

        $http_code = curl_getinfo($ch,CURLINFO_HTTP_CODE);//获取请求状态码
        curl_close($ch);
        if($http_code != '200'){
           return false;
        }
        return true;
    }