Nested do..while loops

[double07]

Hi all,

I'm pretty new to PHP, and I'm stuck.

Basically I'm trying to setup a page where records can be edited etc. So I've basically got it working except for a drop down select list. What happens is that on the first record the drop-down box works fine, however the loop seems to stop then and all I get is a blank drop-down box on the following records.

I hope people can see what I am trying to do.

if ($edit=="true") {
	$catSql = "SELECT * FROM menu_cat";
	$catResult = mysql_query($catSql);
	$catArray = mysql_fetch_array($catResult);

$editSql = "SELECT * FROM menu";
$editResult = mysql_query($editSql);
$editArray = mysql_fetch_array($editResult);

do {
echo "<hr>\n<form action=\"$PHP_SELF?edit=submit\" method=\"get\">\n";
echo "<p>Item Name: <input name=\"menuItem\" type=\"text\" value=\"$editArray[menuItem]\">\n";
echo "<p>Menu Category:	<select name=\"menuCat\" value=\"$editArray[menuCat]\">\n";
	do { 
		echo "<option value=\"$catArray[catType]\">$catArray[catType]</option>\n";
	} while ($catArray = (mysql_fetch_array($catResult)));

echo "</select>";
	echo "<p> Description: <textarea name=\"itemDesc\" cols=\"\" rows=\"3\">$editArray[itemDesc]</textarea>\n";
	echo "<p>Price: (ie 20.00) <input name=\"price\" type=\"text\" value=\"$editArray[price]\">\n";
	echo "<p><input name=\"update\" type=\"submit\" value=\"update\">\n";
	echo "<p><input name=\"delete\" type=\"submit\" value=\"delete\">\n";
	echo "</form>";

} while ($editArray = (mysql_fetch_array($editResult)));
}

Also I see a lot of people using just while instead of do..while. However, when I try to use that the first result from the query is always dropped off, is that normal?

Thanks in advance.

[archangel_617b]

re do {} while () : It is because you would be reading an extra row out before printing the data. It is the same for the nested loop, you should not call mysql_fetch_array() outside that while condition. The outside loop should be like:

$editResult = mysql_query($editSql);
while($editArray = mysql_fetch_array($editResult))
{
    // do some stuff
}

The reason why that cat info only appears once is because you need to reset that result set. As is, it runs to the end of the cat types the first time you use it and then sits there. Just use [man]mysql_data_seek/man like this:

// the rest of the form here
while($catArray = mysql_fetch_array($catResult))
    print("<option value=\"$catArray[catType]\">$catArray[catType]</option>\n");
mysql_data_seek($catResult, 0);    // the important bit
// the rest of your form

Is clear? Good 😃

[double07]

Thanks champ, worked an absolute treat. Thanks for the clear & concise clarification.