How to arrange PHP for loop value? - php

Question

This is my example of seat list arrangements. I have to show some seat alignment changes.
$rows=($data['seat_type']==1)?3:4;
$cols=round($numofseats /$rows) ;
$rowCssPrefix= 'row-';
$colCssPrefix= 'col-';
$seatWidth= 35;
$seatHeight= 35;
$seatCss= 'seat';
$selectedSeatCss= 'selectedSeat';
$selectingSeatCss= 'selectingSeat';
$window_rows = ($data['seat_type']==1) ? array(0,2) :array(0,3);
for ($i = 0; $i < $rows; $i++) {
$seat_w=(in_array($i,$window_rows))?'W':'A';
for ($j = 0; $j < $cols; $j++) {
$seatNo = ($i + $j * $rows + 1);
if($seatNo <= $numofseats)
{
$className = $seatCss . ' '.$rowCssPrefix .$i.' '.$colCssPrefix .$j; if($j % $cols==0) echo '<br>';
if(!in_array($seatNo,$booked_seats)) {
echo'<li class="' . $className.'" style="top:'. ($i *$seatHeight).'px;left:'. ($j *$seatWidth).'px" title="'.$seatNo.$seat_w.'">'.$seatNo.'<input type="checkbox" name="seat[]" value="'.$seatNo.'-'.$seat_w.'"/></li>';
}else{
$className .= ' '.$selectedSeatCss;
echo'<li class="' . $className.'" style="top:'. ($i *$seatHeight).'px;left:'. ($j *$seatWidth).'px">'.$seatNo.'</li>';
}
}
}
}
So I am getting the result like
1 4 7 10
2 5 8 11
3 6 9 12
but it should be
1 6 7 12
2 5 8 11
3 4 9 10
How can I get like this?
Thanks

Answer 1

You should reverse your seat number calculation if you're calculating a number for an odd column.
Change the calculation line to :
$seatNo = (($j % 2) > 0) ? (($rows - $i) + ($j * $rows)) : ($i + $j * $rows + 1);
What's happening here is, we are controlling if the column is odd or even by ($j % 2) > 0; then calculating the number accordingly.
So your code should look like this :
<?php
$rows=($data['seat_type']==1)?3:4;
$cols=round($numofseats /$rows) ;
$rowCssPrefix= 'row-';
$colCssPrefix= 'col-';
$seatWidth= 35;
$seatHeight= 35;
$seatCss= 'seat';
$selectedSeatCss= 'selectedSeat';
$selectingSeatCss= 'selectingSeat';
$window_rows = ($data['seat_type']==1) ? array(0,2) :array(0,3);
for ($i = 0; $i < $rows; $i++) {
$seat_w=(in_array($i,$window_rows))?'W':'A';
for ($j = 0; $j < $cols; $j++) {
// If we are on the first (or 3rd, 5th, odd numbers) column, normally continue numbering,
// But if we are on an even column, reverse the numbering by (($rows - $i) + ($j * $rows)).
$seatNo = (($j % 2) > 0) ? (($rows - $i) + ($j * $rows)) : ($i + $j * $rows + 1);
if($seatNo <= $numofseats)
{
$className = $seatCss . ' '.$rowCssPrefix .$i.' '.$colCssPrefix .$j; if($j % $cols==0) echo '<br>';
if(!in_array($seatNo,$booked_seats)) {
echo'<li class="' . $className.'" style="top:'. ($i *$seatHeight).'px;left:'. ($j *$seatWidth).'px" title="'.$seatNo.$seat_w.'">'.$seatNo.'<input type="checkbox" name="seat[]" value="'.$seatNo.'-'.$seat_w.'"/></li>';
}
else {
$className .= ' '.$selectedSeatCss;
echo'<li class="' . $className.'" style="top:'. ($i *$seatHeight).'px;left:'. ($j *$seatWidth).'px">'.$seatNo.'</li>';
}
}
}
}
?>

Answer 2

The relevant line I assume is
for ($i = 0; $i < $rows; $i++) {
for ($j = 0; $j < $cols; $j++) {
$seatNo = ($i + $j * $rows + 1);
}
}
In order to get an "reverse effect", simply add an if condition to each odd column.
for ($i = 0; $i < $rows; $i++) {
for ($j = 0; $j < $cols; $j++) {
if ($j % 2 == 1) $seatNo = (($rows - $i) + $j * $rows );
else $seatNo = ($i + $j * $rows + 1);
}
}