PHP 远程图片获取到本地

        /*
     * 远程图片获取到本地
     */
    function GrabImage($url){
        if($url != ""){ //如果图片地址为空
            $ext = strrchr($url,'.');   //判断图片的格式
            if($ext != '.jpg' && $ext != '.gif' && $ext != '$png'){
                return false;exit;
            }
            $filename_r = time().rand(10,9000).$ext;    //给图片命名
            $filename = 'getimg/'.$filename_r;
            ob_start(); //打开缓冲区
            readfile($url);
            $imginfo = ob_get_contents();   //获得缓冲区的内容
            ob_end_clean(); //清除并关闭缓冲区
            $fp = fopen($filename,'a');
            fwrite($fp,$imginfo);
            fclose($fp);
        }else{
            return false;
        }
    }
    $start_time = microtime(true);
    GrabImage("http://img4.shougongke.com/Public/advance/53846840dafb4.jpg");
    $end_time = microtime(true);
    $time = round($end_time-$start_time,3);
    echo '程序总共用时'.$time.'秒';
    ?>

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