php - How would I check if a folders contents has changed with PHP?

Question

I've been issued with the task of when an e-mail is sent to a specific e-mail address it should upload it to a folder called 'input' I have to check this folder for changes to see if there are any .PDF files in so I can allow them through to be converted to a .DOC file and be stored in another folder called 'output' and then send it back to the user that e-mailed it, where would I start with this?!

Answer 1

您可以将md5文件夹内容存储在某个位置（数据库、文件、cookies ..），然后如果文件夹内容发生更改，则md5也会更改。

更多关于 md5 的信息。

你可以在这里找到它的功能。

Answer 2

您可以执行以下操作：

<?php
 $filename = '/path/to/input_folder/yourfile.pdf';

 if (file_exists($filename)) {
    //do convert to  .doc
 } else {
    //do something else
 }
?>

只是探索与文件相关的 php 函数