php文件下载代码（支持远程文件下载）

function download($file_dir,$file_name)
//参数说明：
//file_dir:文件所在目录
//file_name:文件名
{
$file_dir = chop($file_dir);//去掉路径中多余的空格
//得出要下载的文件的路径
if($file_dir != '')
{
$file_path = $file_dir;
if(substr($file_dir,strlen($file_dir)-1,strlen($file_dir)) != '/')
$file_path .= '/';
$file_path .= $file_name;
}
else
$file_path = $file_name;

//判断要下载的文件是否存在
if(!file_exists($file_path))
{
echo '对不起,你要下载的文件不存在。';
return false;
}

$file_size = filesize($file_path);

header("content-type: application/octet-stream");
header("accept-ranges: bytes");
header("accept-length: $file_size");
header("content-disposition: attachment; filename=".$file_name);

$fp = fopen($file_path,"r");
$buffer_size = 1024;
$cur_pos = 0;

while(!feof($fp)&&$file_size-$cur_pos>$buffer_size)
{
$buffer = fread($fp,$buffer_size);
echo $buffer;
$cur_pos += $buffer_size;
}

$buffer = fread($fp,$file_size-$cur_pos);
echo $buffer;
fclose($fp);
return true;

}

?>

$file_name = "info_check.exe";
$file_dir = " https://www.111cn.net/";
$file = @ fopen($file_dir . $file_name,"r");
if (!$file) {
echo "文件找不到";
} else {
header("content-type: application/octet-stream");
header("content-disposition: attachment; filename=" . $file_name);
while (!feof ($file)) {
echo fread($file,50000);
}
fclose ($file);
}

?>