Nested while loop problem

Anon

Hi,

I am new to PHP and I am stuck on a problem with the following code. The way it is supposed to work; Based on the number in $portcounter, one table row per 8 drop down boxes should be created. If $portcounter = 32 then I should have 4 rows of 8 drop downs. If $portcounter = 8, I should have one row of drop downs. Currently the code will print out 1 row with 8 drop downs, and the <tr> tag will print, but it won't continue creating the remaining 8 drop downs in the second row. I would appreciate any guidance as to what I am doing wrong.

<form method="POST" action=<?=$PHP_SELF?>>
<table border="1" bgcolor="lightblue" cellpadding="0" cellspacing="0">
<tr> <td>
<?
$portcounter = 16;
$countup = 0;
$portnum = 0;
$perrow = 8;
$rowcount = 0;
$portrows = $portcounter / $perrow;

while ($rowcount < $portrows)
{
$rowcount++;
echo "<tr>";

while ($columncount < $perrow)
{
$columncount++;
echo "<td> <center> Port $columncount <br>";

         while ($countup < $portcounter)
         {
         $countup++;
         if ($countup < 10)
           { $countup2 = "0" . "$countup"; } else { $countup2 = $countup; }
         $optionvalue .= "<OPTION value=\"$countup2\">$countup</OPTION>";
         }
         echo "<SELECT name=\"port$columncount\">";
         echo "<OPTION VALUE=\"\"> </OPTION> <OPTION value=\"00\"> OFF </OPTION>" . "$optionvalue";
         echo "</SELECT> </center> </td>";
}
echo "</tr>";

}
?>

Any clues as to what I am doing wrong would be appreciated!

Thank You,

Spencer

Anon

You need to zeroise your $columncount and $countup variables after each row. At the moment, they are retaining their final values from the first row, which will cause the while conditions on the loops to exit immediately.

Alternatively, use a "for" loop instead of a "while".

Anon

Thank you for the help Martin. The 'for' loop works much better. It will now create multiple rows, but the numbers start over each time. If I have 16 ports I need the first row to be 1 through 8 and the second row 9 through 16. With your help the rows print out 1 through 8 and 1 through 8. It's getting closer. Any suggestions?

Anon

I forgot to attach the revised code.

for ($rowcount = 0; $rowcount < $portrows; $rowcount++)
{
echo "<tr>";

for ($columncount = 1; $columncount <= $perrow ; $columncount++)
{
echo "<td> <center> Port $columncount <br>";

         for ($countup = 1; $countup < $portcounter; $countup++)
         {

         if ($countup < 10)
           { $countup2 = "0" . "$countup"; } else { $countup2 = $countup; }

         $optionvalue .= "<OPTION value=\"$countup2\">$countup</OPTION>";
         }
         echo "<SELECT name=\"port$columncount\">";
         echo "<OPTION VALUE=\"\"> </OPTION> <OPTION value=\"00\"> OFF </OPTION>" . "$optionvalue";
         echo "</SELECT> </center> </td>";
}
echo "</tr>";

}
?>

docdunning

Try this - I've made a few changes here and there. $PHP_SELF doesnt work on my personal web server, so I've tested it with $SCRIPT_NAME instead. I've moved the display of the port values to the top, so they get shown when you enter the script for the second/subsequent times.

<?php
if (isset($port1)) {
echo "$port1, $port2, $port3, $port4, $port5, $port6, $port7, $port8 <br>";
echo "$port9, $port10, $port11, $port12, $port13, $port14, $port15, $port16";
}
?>

<form method="POST" action="<?php echo $SCRIPT_NAME; ?>">
<table border="1" bgcolor="lightblue" cellpadding="0" cellspacing="0">
<tr> <td>
<?
$portcounter = 16;
$countup = 0;
$portnum = 0;
$perrow = 8;
$rowcount = 0;
$columncount = 0;
$portno = 0;
$portrows = $portcounter / $perrow;

$optionvalue = "";
for ($countup = 1; $countup < $portcounter; $countup++) {
$countup2 = sprintf("%02d",$countup);
$optionvalue .= "<OPTION value=\"$countup2\">$countup</OPTION>";
}

for ($rowcount = 0; $rowcount < $portrows; $rowcount++) {

echo "<tr>";

for ($columncount = 1; $columncount <= $perrow ; $columncount++) {

$portno ++;
echo "<td> <center> Port $portno <br>";   
echo "<SELECT name=\"port$portno\">";
echo "<OPTION VALUE=\"\"> </OPTION> <OPTION value=\"00\"> OFF </OPTION>","$optionvalue";
echo "</SELECT> </center> </td>";

}

echo "</tr>";

}
?>

Anon

Thank you very much Martin! Your code works great and is much simpler to follow.

Spencer