How to solve the problem that large php files cannot be downloaded

The solution to the problem that large PHP files cannot be downloaded: first obtain the file name to be downloaded; then set the maximum execution time of the script through the "set_time_limit(0);" method; and finally clear the cache.

Recommendation: "PHP Video Tutorial"

I am currently working on a photo download system and need to download customer photos Come down, and then perform PS photo editing, but the downloaded file must be the camera's original file CR2 file. This type of file is generally relatively large. Generally, a photo is too small, about 30M. I didn’t pay attention to it after the download was completed. Now, the photos downloaded by the reaction system cannot be opened by Photoshop. At first, I thought it was because the software did not have camera Raw installed. After installing the plug-in, I found that it still could not be opened. Finally, I compared the downloaded picture with the picture before uploading. The downloaded picture was much smaller than the original picture. At this time, I found that the downloaded picture was probably incomplete. After searching on Baidu, I found that it was a problem with the execution time of the PHP script. The general default is 30 seconds, and the problem can be solved after setting a configuration.

set_time_limit(0); means no time limit, so I will post my own download code below. You can use this function directly

//fname为要下载的文件名
//$fpath为下载文件所在文件夹，默认是downlod
function download($fpath="download/"){
    //获得要下载的文件名
    $pathinfo=pathinfo($fpath);
 
    $filename=$pathinfo['filename'].'.'.$pathinfo['extension'];
 
 
    //避免中文文件名出现检测不到文件名的情况，进行转码utf-8->gbk
//    $filename=iconv('utf-8', 'gb2312', $fname);
    $downpath=$fpath;
    if(!file_exists($downpath)){//检测文件是否存在
        echo "文件不存在！";
        die();
    }
    //    //设置脚本的最大执行时间，设置为0则无时间限制
    set_time_limit(0);
    $fp=fopen($downpath,'rb');//只读方式打开
    $filesize=filesize($downpath);//文件大小
//    echo $filesize;
//    die;
    //返回的文件(流形式)
    header("Content-type: application/octet-stream");
    //按照字节大小返回
    header("Accept-Ranges: bytes");
    //返回文件大小
    header("Accept-Length: $filesize");
    //这里客户端的弹出对话框，对应的文件名
    header("Content-Disposition: attachment; filename=".$filename);
    //清除缓存
    ob_clean();
    flush();
    //设置分流
    $buffer=4096;
    //来个文件字节计数器
    $count=0;
    while(!feof($fp)&&($filesize-$count>0)){
        //设置文件最长执行时间
        set_time_limit(0);
        $data=fread($fp,$buffer);
        $count+=$data;//计数
        echo $data;//传数据给浏览器端
    }
 
    fclose($fp);
 
}

I hope it can help you solve the problem

The above is the detailed content of How to solve the problem that large php files cannot be downloaded. For more information, please follow other related articles on the PHP Chinese website!