如何使用php和javascript擦除文本文件的内容

Question

I have a webpage that displays the contents of a text file. I want to make a button that will clear the contents of that text file. I know that the contents of a file can be erased by using php, but I've been having trouble finding a way to make a button that will do this because php is server side. Is there a good way to do this with Javascript?

Answer 1

A file, on the server, can only be deleted by software running on the server. Client side JavaScript can't do that. If it could, then any old Joe could delete any content from any website.

You could use client side JavaScript to make an HTTP request that the server (usually via a server side programming language (which could be JavaScript (via Node, Classic ASP, etc), PHP or something else)) would interpret as an instruction to delete the file … but you could equally just use an HTML form to make a POST request.

Answer 2

No, you cannot modify the user's disk from within javascript. However, flash or silverlight might be able to do it. I shudder to think of the possibilities.

edit : Oh, you're talking about a file on the server? The server can do that. The client can only instruct the server to do it on their behalf.

Answer 3

You no need the Javascript. Try something like this:

<form action="file.php" method="get">
   <button name="button_name" value="clear" />
</form>

And into your php file you need put something like this:

file_put_contents($file, ''); //write empty string to file