PHP getting selected table rows from checkboxes - php

Question

I have a PHP form where a table is created of all files in a folder on the server, and each row created is assigned a checkbox which will be used to decide which files are to be deleted or shared etc. Each row is given a name checkbox[$rownumber] to distinguish each, and then when a button is clicked, for the moment to ensure I can get it working, it just prints the rows that are selected - but I can't get this working.
Initially, as rows are created in the table from the server, this is the code, which correctly creates them as I wish
<?php
if(isset($_REQUEST['deleteFile']))
{var_dump($_REQUEST);
if(isset($_POST['checkbox']))
{
print_r($_POST);
}
}
?>
<form name="mainHomescreen" action="MainHomescreen.php" method="POST">
<nav>
<input type="text" name="Search" value="Search" style = "color:#888;" onFocus="inputFocus(this)" onBlur="inputBlur(this)"/>
</nav>
<sidebar>
<input type="button" value="Create Folder" onClick="createFolder()"/>
<input type="button" value="Download Selected Files/Folders" onClick=" "/>
<input type="button" value="Encrypt Selected" onClick="encrypt()"/><br>
<input type="button" value="Share Selected" onClick="shareFolder()"/>
<!-- upload a file -->
<div id="fileUpload">
<div id="uploadPopup">
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" id="uploadForm" method="post" name="uploadForm" enctype="multipart/form-data">
Select file to upload: <input name="fileUpload" type="file" /><br />
<input type="submit" value="Upload File" name="submitFile"/>
</form>
</div>
</div>
<input type="button" name="upload" value="Upload File" onClick="showUpload()"/>
<input type="submit" value="Delete" name="deleteFile"/>
<input type="button" value="Rename" onClick=" "/><br>
<input type="button" value="Password Protect Folder/ File" onClick=" "/><br><br>
</sidebar>
<article>
<span class="error"><?php echo $error;?></span>
<table id="detailView" style="width:100%">
<!-- php to create table -->
<?php
//open file names
$dir = opendir("/home/a1962403/public_html/files");
$filearray = array(array(array()));
echo '<table cellpadding="10" cellspacing="0" style="width:100%">';
echo '
<tr>
<th> </th>
<th>File</th>
<th>Date</th>
<th>Size</th>
</tr>
';
$rownumber = 0;
//List files in directory
while (($file = readdir($dir)) !== false)
{
//gets the file date, string needed decoding otherwise throws error.
$date = #filemtime($file);
$date = date("F d Y H:i:s.", filemtime(utf8_decode("/home/a1962403/public_html/files/$file")));
$size = filesize("/home/a1962403/public_html/files/$file") . ' bytes';
$rownumber = $rownumber + 1;
//prints a table row
echo '<tr class="bottomline">';
echo "<td><input type='checkbox' name='checkbox[$rownumber]' value='[$rownumber]' </td>";
echo "<td>$file</td>";
echo "<td>$date</td>";
echo "<td>$size</td>";
echo '</tr>';
}
echo '</table>';
closedir($dir);
?>
</article>
</form>
</body>
</html>
From this, I have a submit button called 'deleteFile', which I am wanting to use to as I said for the moment, just get what is selected to ensure it works, but it's not actually giving me any output so any help would be greatly appreciated.

Answer 1

Your row formatting may be the problem
echo "<td><input type='checkbox' name='checkbox[$rownumber]' value='[$rownumber]' </td>";
Change it to:
echo "<td><input type='checkbox' name='checkbox[" . $rownumber . "]' value='". $rownumber . "' </td>";
And because your are numbering from 0 up you could also just use checkbox[] as a name.
It would help to this form live.

Answer 2

You are right to use isset when determining whether a checkbox is checked or not, but you are using differring names:
isset($_POST['checkbox'])
will return true if
<input type="checkbox" name="checkbox" />
is checked.
You have to refer to posted inputs using their names in the $_POST array.
In this case, you need to check for checkbox[$rownumber], which, as is seemingly trivial, requires you to know the row numbers when posting:
PHP code
if (isset($_POST["checkbox[$rownumber]"]))
{
// This checkbox is checked
}
If you don't know the exact input names, you might want to iterate through the $_POST array:
PHP code
foreach ($_POST as $input_name => $input_value)
{
if (strpos($input_name, 'checkbox') !== false)
{
// This input's name contains the substring 'checkbox'
}
}
Note the type-strict comparison at strpos.