PHP强制性文件下载

[php]代码库

/******************** 
*@file - path to file 
*/ 
function force_download($file) 
{ 
	if ((isset($file))&&(file_exists($file))) { 
		header("Content-length: ".filesize($file)); 
		header('Content-Type: application/octet-stream'); 
		header('Content-Disposition: attachment; filename="' . $file . '"'); 
		readfile("$file"); 
	} 
	else { 
		echo "No file selected"; 
	} 
}