Help with deleting items in a list, using PHP - php

Question

I have a list of email addresses in a table, which is populated via an SQL query. Next to each email address, I've placed a submit button which I want to use to delete the email address that appears in that particular table row.
I thought of appending the email address to the name of each delete button, with the hope that it will take me in the right direction.
while($row = mysql_fetch_array($result))
echo "<tr><td>".$row['email_adress']."</td><td><input type=\"submit\" value=\"Delete\" name=\"delete".$row['email_adress']."\"></td></tr>";
I'm wondering how to use the delete button for each entry. Any help?

Answer 1

I think the issue is that you are attempting to use submit buttons to contain data when submit buttons are not meant to contain data. Well they can and people do use them that way, but I prefer to use submit buttons to determine how to handle the data rather than to be the data in the submit. There are two basic methods that I think would be a fair extension to what you are trying to do.
1.) Use links to issue the delete
2.) Use the submit button to issue the delete, but include a hidden form field to contain the email address to delete.
In the case of using a link you don't have to deal with a form, but I don't know about the rest of the page. If you are sending any other data, then a form is the ideal way. If you are just sending a single piece of data to delete the email, then I suggest a link. My recommendation come from a functional perspective. You might have a UI reason to a button that I don't know about.
In the case of using a form, the hidden field should contain the primary key (untested):
while($row = mysql_fetch_array($result)) {
echo "<tr>
<td>".$row['email_adress']."</td>
<td><form action="some/uri/to/something">
<input type=\"hidden\"
name=\"emailAddress\" value=\"{$row['email_adress']}\"/>
<input type=\"submit\" value=\"Delete\"
name=\"delete".{$row['email_adress']}."\">";
</form>
</tr>
</td>";
}
You have to create a form around each submit else every hidden field in the form would be submitted telling you nothing about which email to delete. You can do many more things with the submit by using Javascript, but the simple method would be to just use a link -- forget about forms.

Answer 2

If a button is absolutely a must, you could output a small form for each button and add a hidden field containing the id (or email, if you insist). The form would submit the id or address in the hidden field, which you pick up in your processing script and run your delete query.
edited to remove a portion of the answer that was determined to be an unwise method

Answer 3

so I've been messing around with this code trying to get a "prefetch browser add-on" to trigger something and kill my database... but I havn't been able to trigger anything yet... but I'd sure like to.
<?php
//CREATE AND POPULATE DB
if(!file_exists('a.sqlite')){
$db = new SQLite3('a.sqlite');
$db -> exec("CREATE TABLE test (idx INTEGER PRIMARY KEY, number INTEGER NOT NULL);");
for($i=0;$i<9;$i++){
$db -> exec("INSERT INTO test (number) VALUES (".(rand(1000,9999)).");");
}
}else{
$db = new SQLite3('a.sqlite');
}
//PERFORM DELETE FROM HREF
if(isset($_REQUEST['delete'])){
$db -> exec("DELETE FROM test WHERE idx = ".$_REQUEST['delete'].";");
}
//SHOW CONTENTS OF BASE OR DELETE DB FILE
$result = $db->query('SELECT * FROM test');
while ($row = $result->fetchArray()) {
echo "<a href='test.php?delete=".$row['idx']."'>".$row['number']."</a></br>";
}
?>

Answer 4

Yes, you could do it like this but that would require to either execute the query again on the form's target page and then check for every combination of "delete".$row['email_adress'] or use a construction like this:
foreach ($_REQUEST as $key => $dummy)
if (substr($key,0,6) == 'delete')
delete_entry(substr($key,6));
However, if you simply swap value and name...
<input type=\"submit\" name=\"Delete\" value=\"".$row['email_adress']."\">
...you can just check $_REQUEST['Delete'] to find out which address button has been clicked.

Answer 5

... I'm still not sure about displaying peoples emails on web pages unless it's company internal.. I gather we are in a secure company back office?
I'd go for the:
<a href=my_page.php?delete_email_id=456>email</a>
probably with some annoying javascript for the confirm
email
and catch it with a
if(isset($_REQUEST['delete_email_id']){ SQL UPDATE ENTRY...}
at the top of my_page.php