Dynamic Variables?

[Nicholas]

I it possible to have variables concatenated together?

For instance, in a loop you've got something like this:

 

$variable = "multipleSomethings";
for($num=1;$num<=10;$num++) {
$variable.$num = "multipleSomethings" . $num;
}

echo $variable1; // "multipleSomethings1"
echo $variable2; // "multipleSomethings2"

 

See what I'm saying?

 

Now try to understand my code.

 

case 'pendCalendar':
// Get all the calendar events that haven't been accepted yet, and display them
print '<div class="para">' .
		'<h1>Pending Calendar Additions</h1>' .
		'The following are requests from coaches which have not yet been approved.<br />' .
		'Please check the information for accuracy, and then decide whether or not to accept the request.<br />' .
		'<strong>Be sure to check whether there are existing events that might cause a confliction.</strong><br /><br />' .
		'<form action="admin.php?action=updateCalendar" method="post">' .
		'<table cellpadding="0" cellspacing="0" style="border: 1px solid #666;" width="100%">' .
			'<tr>' .
				'<td style="background: #999; padding: 3px;" width="25%"><strong>Event Date:</strong></td>' .
				'<td style="background: #999; padding: 3px;" width="20%"><strong>Event Location:</strong></td>' .
				'<td style="background: #999; padding: 3px;" width="30%"><strong>Event Description:</strong></td>' .
				'<td style="background: #999; padding: 3px;" width="25%"><strong>Accept?</strong></td>' .
			'</tr>';

guestLogin($username,$password);
$query = mysql_query( "SELECT * FROM calendar07 WHERE accept='0' " );
$num = 1;
while($fetch = mysql_fetch_assoc($query)) {
	print '<input name="hidden_' . $num . '" type="hidden" value="' . $fetch['id'] . '>';
	print '<tr>' .
				'<td style="padding: 5px;" valign="top">' . $fetch['month'] . ' ' . $fetch['day'] . ': ' . $fetch['time'] . '</td>' .
				'<td style="padding: 5px;" valign="top">Field ' . $fetch['field'] . '</td>' .
				'<td style="padding: 5px;" valign="top"><em>Requested by: </em>' . $fetch['leader'] . '<br />' .
				'<em>Brief Summary: </em>' . $fetch['desc'] . '</td>' .
				'<td style="padding: 5px;" valign="top"><select name="event_' . $num . '">' .
					'<option value="accept">Accept Event</option>' .
					'<option value="deny">Refuse Event</option>' .
				'</select>' .
				'</td>' .
			'</tr>';
}

print '<tr>' .
		'<td colspan="4" style="text-align: right;"><input type="submit" value="Submit" /></td>' .
		'</tr>' .
		'</table>';
break;
case 'updateCalendar':
$num = 1;
do {
	if (isset($_POST["event.$num"])) {
		$accept.$num = $_POST["event.$num"];
		$id.$num = $_POST["hidden.$num"];
		$num++;
		$set = 'true';
	} else {
		$max = $num;
		$set = 'false';
	}
} while($set='true');

break;

 

[Jessica]

Yes, it's possible.

No, I won't try to sort through your code if you didn't post a specific problem, error, or issue.

I do see one immediate error.

while($set='true'); will always be true. = is assignment, == or === is comparison.

[Nicholas]

Thanks for the quick response. And good eye on the =/== bit.

Technically, what I posted was exactly the area that you need to see. But I'll trim it down for clarity...

 

Better?

case 'pendCalendar':
// Get all the calendar events that haven't been accepted yet, and display them
...
<form action="admin.php?action=updateCalendar" method="post">
...
// Connect to the database etc...
// The fun part: looping through the results
$num = 1;
while($fetch = mysql_fetch_assoc($query)) {
	<input name="hidden_' . $num . '" type="hidden" value="' . $fetch['id'] . '> // Notice: hidden_$num will be dynamic
	<td style="padding: 5px;" valign="top">
		<select name="event_' . $num . '"> // Again, a dynamic name
			<option value="accept">Accept Event</option>
			<option value="deny">Refuse Event</option>
		</select>
}
break;
case 'updateCalendar':
$num = 1;
do {
	if (isset($_POST["event.$num"])) {
		$accept.$num = $_POST["event.$num"];
		$id.$num = $_POST["hidden.$num"];
		$num++;
		$set = 'true';
	} else {
		$max = $num;
		$set = 'false';
	}
} while($set='true');

break;

 

[trq]

Yes its possible, but I don't quite see the relevance with your code.

 

Also, note that booleans are not strings. eg;

 

$set = 'true';

 

should be...

 

$set = true;

 

And this....

 

} while($set='true');

 

will cause an infinite loop. Should be....

 

} while($set);

[Jessica]

You still haven't told us what the problem is.

[Nicholas]

jesirose: If there aren't any apparent code errors, I guess there isn't a problem. I just assumed that this wouldn't work as I coded it as pseudo-code, not expecting it to actually be correct.

[Jessica]

Well we posted some errors you had. The easiest way to find out if it works is to try it. Then when it doesn't, you address the errors you get. You could have done that in less time then it took to post and wait for us to reply

[ToonMariner]

I think the guy is looking for variable variables....

 

http://uk.php.net/manual/en/language.variables.variable.php

 

and what he is trying to achive all lies within the first loop

 

so this should do the trick...

 

$var = "variable$num";
for($num=1;$num<=10;$num++) {
$$var = "multipleSomethings" . $num;
}

 

you will have to adjust the code after that to reflect the variable names accordingly.

 

[Nicholas]

Well it seems there are errors in the code.

After enabling all errors, and the having them displayed...

 

Notice: Undefined variable: accept in ... on line 100

 

error_reporting(E_ALL);
ini_set('display_errors','On');
$num = 1;
do {
if (isset($_POST["event.$num"])) {
	$accept.$num = $_POST["event.$num"];
	$id.$num = $_POST["hidden.$num"];
	$num++;
	$set = true;
} else {
	$max = $num;
	$set = false;
}
} while($set);

guestLogin($username,$password);
for($num = 1;$num <= $max; $num++) {
if ($accept.$num == 'accept') { // Line 100
	$query = "UPDATE calendar07 SET accept = '1' WHERE id='" . $id.$num . "'";
	$result = mysql_query($query);
	if ($result) {
		print 'Calendar updated for event id ' . $id.$num . '. The event is ' . $accept.$num . 'ed.';
	}
}
}			

[Jessica]

Can you tell us which line is 100?

Try doing it the way Toon posted.

[Nicholas]

First I'll need to understand variable variables...

The example on that page seems as if you could achieve the same thing with .=  .

 

Can someone explain further these lines:

 

At this point two variables have been defined and stored in the PHP symbol tree: $a with contents "hello" and $hello with contents "world". Therefore, this statement:

<?php
echo "$a ${$a}";
?>

produces the exact same output as:

<?php
echo "$a $hello";
?>

 

i.e. they both produce: hello world.

 

-------------------------------------------------------

I don't want seperate variables... Would echoing $a give "hello world"?