我在php中打开pdf文件，如何保护它？ 没有人既不能下载也不能打印

I run PDF file through localhost in php there is a option in browser of printing the PDF and I dont want it to be print. Here is my code:

header('Content-type: application/pdf');
readfile('The C# 4.0 complete reference.pdf');
die();

kindly help me

try this code

   <?php
    header("Content-type:application/pdf");

    // It will be called downloaded.pdf
    header("Content-Disposition:attachment;filename='downloaded.pdf'");

    // The PDF source is in original.pdf
    readfile("original.pdf");
    ?>