echo delete $file returning Fatal Error

Question

bradly.spicer 47 Posting Whiz in Training

12 Years Ago

Hello,

I'm posting again regarding as to why my php code won't process the delete.php

Index.php:

<div id="DeleteFile">
Delete A Script:
<form action="delete.php">
</html>
<?
$path = "uploads/";
$handle = opendir($path);   
echo '<select>';     
while ($file = readdir($handle)) {
    if (substr($file,0,1) != ".") {
    echo "<option value ='$file'>$file</option>";
    }   
}
echo '</select>';
closedir($handle);
?>
<html>
<input type="submit" action="delete.php"/></form>
</div>
</div>
</body>
</html>

So thats my Index page, and I can only assume it works as it takes me to url.co.uk/delete.php?

However, It doesn't actually delete the file.

Delete.php:

<html><link href="stylesheet.css" rel="stylesheet" type="text/css">

<head>

</head>

<body>
</html>
<?php
function delete() {

    echo delete('$file');
    echo "The file $file has been deleted"; 
}
?>

Sorry for bothering you guys, thanks.

php

4 Contributors
19 Replies
217 Views
23 Hours Discussion Span
Latest Post 12 Years Ago Latest Post by adam.adamski.96155

Bachu 45 Newbie Poster

12 Years Ago

First you check, is posted file exist or not

EXg:

$yourFile = "uploads/".$_POST['selectBoxName'];
$checkFile = fopen($yourFile, 'w') or die("can't open file");
fclose($checkFile);

If file exist, then

unlink($yourFile);

pritaeas 2,194 ¯\_(ツ)_/¯

12 Years Ago

First off, you'll need to generate correct HTML code. Next, I suggest you look up how a form works. There are a lot of examples/tutorials to be found.

adam.adamski.96155 43 Junior Poster

12 Years Ago

Index.php - fix your HTML tags, you close the page before you open it. You haven't named your select element and won't be able to access the selected file. Your form has no method.
Delete.php looks ok, but fix index before you worry about it.
You should write print_r($_POST); die(); at the top of delete.php and don't remove it until you see the filename as you want it to be sent to the function.

You need to learn how to build a form in HTML, then how to grab the data entered using PHP. This is the bread and milk of PHP, there are multitudes of tutorials online.
Good luck! :D

adam.adamski.96155 43 Junior Poster

12 Years Ago

You have discovered variable scope:
http://www.homeandlearn.co.uk/php/php8p2.html
http://www.w3schools.com/php/php_variables.asp
See if you can work it out, let me know if you get stuck :)
Good luck!

adam.adamski.96155 43 Junior Poster

12 Years Ago

Hey that's great! Be aware that $_GET is a global by default, so you could reference it in your function, also you could have passed the variable to the function (prefered method) -

function delete($file){//everytime you want function to access variable... 
    if (unlink($file)){//it must referenced by the variable in the function declaration - ($file).
    //do functionary things
    }
}

and call the function with the variable passed:

$filename = $_GET['filename'];//define $filename
delete($filename);//send $filename to function.

You could also have passed $_GET['filename'] to the function -

delete($_GET['filename']);

Well done :D

bradly.spicer commented: Helpful :) +0

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pritaeas 2,194 ¯\_(ツ)_/¯ Moderator Featured Poster · Answer 1 · 2012-10-10T11:20:25+00:00

That's because in delete.php $file has no value, and although you define a function, it is never executed.

bradly.spicer 47 Posting Whiz in Training · Answer 2 · 2012-10-10T11:29:04+00:00

I was under the impression it would take this from a file previously loaded. So to make it automatically delete whats inside the drop down box would I need to put that PHP function within the index.php page and in action call the function rather than a page?

Thanks again,

Bradly

edit: So I just tried to make these changes after putting the delete.php snippet above the code:

<form action= delete();>
</html>
<?php
$path = "uploads/";
$handle = opendir($path);   
echo '<select>';     
while ($file = readdir($handle)) {
    if (substr($file,0,1) != ".") {
    echo "<option value ='$file'>$file</option>";
    }   
}
echo '</select>';
closedir($handle);
?>
<html>
<input type="Submit" value="Delete File" action='delete();'/></form>

I have a feeling I am doing it wrong haha...

adam.adamski.96155 43 Junior Poster · Answer 3 · 2012-10-10T12:04:20+00:00

Hey there, you really need to learn this step by step.
The first page is the form page that allows the user to select the file that is to be deleted. This page will have a submit button which when clicked will redirect to the URL specified in the action="delete.php" of the form tag.
delete.php needs to be ready to catch the data posted with the form, in this case, the filename to delete. Then it needs to check if the file/path actually exists and respond appropriately.
Take it step by step, check each part is working before you move on to the next stage. If you are really trying and get stuck, post your problems here and people will help.

bradly.spicer 47 Posting Whiz in Training · Answer 4 · 2012-10-10T12:16:51+00:00

Thank you for your response everybody, I'm going through my code commenting and making it a bit easier to read at this minute. However I will cleanup the forms etc. Thats due to me chopping and dicing up what I had previously tweaked with and left debre about.

Ok, so I have improved on my code and done as you guys have said :)

I have looked up unlink and made a function which deletes a file when activated.

<?php
function delete() {
    $filename = './uploads/filetodelete.txt';
    if (@unlink($filename)) {
        echo 'File <strong>' .$filename. ' has successfully been deleted.';
        } else {
        echo 'Cannot Delete file';
        }
    }
?>

So the way I see it is $filename = '$file'; but as you guys said I have to carry the information sent from the form into delete.php, I guess this is where I am going to have issues. I've looked online and most places suggest using Mysql, which I would like to avoid.

Thanks in advance guys,

bradly.spicer 47 Posting Whiz in Training · Answer 5 · 2012-10-10T13:21:26+00:00

Sorry, I can't edit my previous post as I have been able to before. Basically I was wondering if I could just get a little input on what I've done.

So the form itself Creates a list of directories correctly and the delete.php deletes whatever I put in the $filename.

SO, I named the option name as 'filename'.

Index.php:

<form action="delete.php">
</html>
<?php
$path = "uploads/";
$handle = opendir($path);   

    echo '<select>';     
    while ($file = readdir($handle)) {
        if (substr($file,0,1) != ".") { 
        echo "<option name='filename' value ='$file'>$file</option>";
        }   
    }

echo '</select>';
$filename = $_POST['filename']; 
closedir($handle); // Closes the directory so it is quicker 

?>

<!-- This php is the form which grabs filenames from the directory -->

<html>
<input type="Submit" value="Delete File"/></form>

Delete.php:

<?php

$filename = $_GET['filename']; 

function delete() {
    $filename = './uploads/filetodelete.txt';
    if (@unlink($filename)) {
        echo 'File <strong>' .$filename. ' has successfully been deleted.';
        } else {
        echo 'Cannot Delete file';
        }
    }
?>

I also looked at Bachov's method. Where it takes the $_Post[''];

but its throwing an arror saying can't open file. Which I believe is because I'm not sending or receiving data accross pages properly?

Thanks for your patience everyone. I believe I am getting closer.

bradly.spicer 47 Posting Whiz in Training · Answer 6 · 2012-10-10T15:31:36+00:00

Hey adam, sorry for the misunderstanding about closing the page before you open it. Thats because it was a seperate part.

Here is the site: Cpanel.minepress.co.uk

Ok so I think I got it semi working :)

I did <select name="item"> which would be the area you were talking about and I also changed the form to Method="GET".

http://cpanel.minepress.co.uk/delete.php?item=employers-banner2.png

It now goes to delete.php?item=thefilenamehere

However I think the delete.php function is broken

as when I go there all I get is Array()

Which I think wrong because the array is meant to appear inside that?

Delete.php:

<html><link href="stylesheet.css" rel="stylesheet" type="text/css">

<head>

</head>

<body>
    <?print_r($_POST); die();?>
</html>

<?php
$filename = $_GET['filename']; 
    if (@unlink($filename)) {
        echo 'File <strong>' .$filename. ' has successfully been deleted.';
        } else {
        echo 'Cannot Delete file';
        }
?>

adam.adamski.96155 43 Junior Poster · Answer 7 · 2012-10-10T16:04:41+00:00

Haha, good to see you still at it :D
This one problem is simple, you added a 'get' method to the form, yet I told you to echo 'post', you can either change the form method to post, or the variable to $_GET.

bradly.spicer 47 Posting Whiz in Training · Answer 8 · 2012-10-10T16:55:28+00:00

Hey again! So I changed the form to Post method :P Which I have to say that was a huge dumb mistake on my end :)

Now whenever I go to http://cpanel.minepress.co.uk/delete.php from the index it posts the filename inside the array.. YAY :D

However its stopped putting ?item= at the end of it AND its not actually deleting the file.

URL:
http://cpanel.minepress.co.uk/delete.php

Contents:
Array ( [item] => employers-banner2.png )

adam.adamski.96155 43 Junior Poster · Answer 9 · 2012-10-10T17:05:37+00:00

It stopped putting your variables into the URL when you changed from get to post. Have a look at the code that declares $filename, the problem is clear :D

bradly.spicer 47 Posting Whiz in Training · Answer 10 · 2012-10-10T17:17:14+00:00

I've been doing this to long -.- haha,

I'm completely lost as to why the $filename declare is a problem? I also think I have it slightly messed up again.

$filename = $_GET['file']; 

is now 

    $filename = $_POST['file'];

But I thought on the delete.php page it should be GET because it is grabbing the data that index.php is POST ing?

Forgive me for these stupid mishaps haha, I'm determined to get this working

adam.adamski.96155 43 Junior Poster · Answer 11 · 2012-10-10T19:05:53+00:00

There are two methods available with a HTML form, "get" and "post". If the form is using get method, the variables will be in the $_GET array for PHP to use, but they will also be in the URL in &name=value pairs. If the form is "post" method, the variables will be in the $_POST array and not in the URL.

bradly.spicer 47 Posting Whiz in Training · Answer 12 · 2012-10-10T19:18:18+00:00

I changed them all to get so that it was appearing in the URL.

I have just realised Delete.php I made a function. But I'm not actually calling to use the function am I?

    <?php
        $filename = $_GET['filename']; 
    function delete() {
        if (@unlink($filename)) {
            echo 'File <strong>' .$filename. ' has successfully been deleted.';
            } else {
            echo 'Cannot Delete file';
            }
        }
delete();        
echo'<br>';
      print_r($_GET);
?>

edit:

So It's not actually finding the file?

bradly.spicer 47 Posting Whiz in Training · Answer 13 · 2012-10-11T09:15:14+00:00

So if I'm getting this right, your saying I haven't

Got the function laid out correctly
Got the variables being defined as to whether or not they are local/global/static?

edit:

Warning: unlink() [function.unlink]: No such file or directory in /home/xtrapsp/public_html/Cpanel/delete.php on line 17



    <?php

$filename = $_GET['filename'];  


 function delete() {
   global  $filename;

        if (unlink($filename)) {
            echo 'File <strong>' .$filename. ' has successfully been deleted.';
            } else {
            echo 'Cannot Delete file';
            }
        }
    delete();        
    echo'<br>';
          print_r($_GET);

    ?>

bradly.spicer 47 Posting Whiz in Training · Answer 14 · 2012-10-11T09:55:19+00:00

Fixed it :D Thanks very much for all of your help everybody!