Merging PHP IF statements to a single statement or function - php

Question

So I have some code that it seems that I have to repeat over and over again for $round == P,1,2 and A. Is there any I can achieve this without producing redundant code?
I'm thinking of writing a function that simply swaps through through all 3 possible $round variables that can be available and echoing the relevant information. Any idea on how to achieve this?
The other information will remain the same - its only $round that will change,
// determine previous round
if($round == "P") echo "";
// if we are in round 1, look up round P bookings
if($round == "1")
{
$sql = "SELECT
*
FROM ts_request
INNER JOIN ts_day
ON ts_request.day_id = ts_day.id
INNER JOIN ts_period
ON ts_request.period_id = ts_period.id
INNER JOIN ts_allocation
ON ts_request.id = ts_allocation.request_id
WHERE ts_request.round=:round
AND ts_request.dept_id=:dept
ORDER BY ts_request.module_id ASC";
$stm = $pdo->prepare( $sql );
$stm->execute( array( ':round' => 'P', ':dept' => $loggedin_id ) );
$rows = $stm->fetchAll();
foreach ($rows as $row)
{
echo '<tr align="center">';
echo '<td>'.$row['module_id'].'</td>';
echo '<td>'.$row['day'].'</td>';
echo '<td>'.$row['period'].'</td>';
echo '<td>';
$sql = "SELECT * FROM ts_roompref
WHERE request_id=:id";
$stm = $pdo->prepare( $sql );
$stm->execute( array( ':id' => $row['request_id']) );
$rows2 = $stm->fetchAll();
foreach ($rows2 as $row2)
{
if ($row2['room_id']=="0")
{
echo "Any<br>";
}
else
{
echo $row2['room_id'].'<br>';
}
}
echo '</td>';
echo '<td>'.$row['status'].'</td>';
echo '</tr>';
}
}
// if we are in round 2, look up round 1 bookings
if($round == "2")
{
$sql .= "";
}
foreach ($rows as $row)
{
// echo results here
};
// if we are in round A, look up round 2 bookings
if($round == "A")
{
$sql .= "";
}
foreach ($rows as $row)
{
// echo results here
};

Answer 1

This may help.
$roundsInOrder = array('P', '1', '2', 'A');
$roundKey = array_search($incomingRoundLetter, $roundsInOrder);
if ($roundKey !== false || $roundKey != 0) {
$roundToQuery = $roundsInOrder[$roundKey - 1];
// your other code snipped
$stm->execute( array( ':round' => $roundToQuery, ':dept' => $loggedin_id ) );
//more code here
}
What this code does:
It sets up the rounds in order. Then, it searches the rounds for the incoming round. We really want the key. Then, the if statement checks to a) make sure we have actually found the round and b) the round is not the first one (0 = P) because we don't want to do any query then. Finally, the $roundToQuery gets the value out of the rounds that is directly before the current key.

Answer 2

I think what you are searching for is the switch() function in php.
Here is a nice and simple tutorial on how to use it:
http://www.tizag.com/phpT/switch.php
Hope this helps.

Answer 3

"Swapping" already exists, it's called "switch statement". In your case it should look like this:
switch($round) {
case "P":
//code
break;
case "1":
//code
break;
case "2":
//code
break;
case "A":
//code
break;
default:
//code, when value of $round doesn't match any case
break;
}