return within a function within a function.

[pablodelapena]

Ok, This is HOPEFULLY simple question so i put it in noobs.

Iam fairly new at PHP OOP, however im giving it ago and seeing what i come up with. During this change to more sophisticated programming i decided that id use some more functions. One of which id seen used alot is the return() function. However, inevitably i ahve run into problems.

I havea function which determins which type of date format a user would like according to their account settings in MySQL.

It will then return the approriate setup.

However, I wish to sue this function within a while loop which is in another function. If i dont have the 1st function the loop runs fine. however as soon as i add my new fancy function it stops after one run. Fancy taking a peak and seeing if there is anything wrong?

//fancy timestamp function :) oooooooohhh


	function PrepareTimestamp($day,$month,$year) {
	global $SQL;

		if ($_SESSION['SPuserID'] == "guest") {
		//default
			$this->timestamp = "".$month."/".$day."/".$year;
		} else {
		//user specific
			$query = "SELECT time_format 
FROM userinfo WHERE username='".$_SESSION['SPuserID']."'";
				$SQL->query_db($query);
				$tformat = $SQL->fetch_row();

			if ($tformat['time_format'] == "ddmmyyyy") {
			$this->timestamp = "".$day."/".$month."/".$year;
			} else {
			$this->timestamp = "".$month."/".$day."/".$year;
			}

		}

		return $this->timestamp;

	} // End PrepareTimestamp();

//while loop function bla bla

function loop() {

while (something is true) {

echo "hello world";
echo PrepareTimestamp();

}

Obviously not the actualy function with the loop but its the idea... 🙂

[laserlight]

The return keyword isnt a function, it is a language construct.
When return is used in a function (say function X() ), control (the flow of the program) is passed back to the caller.
The caller is the function (or whatever code) that called function X().

I cant see anything wrong with your code snippet, aside from some typos (e.g. left out arguments for PrepareTimestamp(), missing closing brace)
But the problem is that the critical part of the loop, i.e. the loop condition, has been replaced with "something is true", making it impossible to tell if that "something" is the whole problem.

[pablodelapena]

yeah sorry i just couldnt be bothered typing it out so well here is the loop as is in my function:

				while ($row = $SQL->fetch_row()) {

				if ($_GET['box'] = "inbox") {
					if (strlen($row['from_user']) > 18) {
					$user = substr($row['from_user'],0,15) . "...";
					} else {
					$user = $row['from_user'];
					}

					$is_online = "SELECT SID from sessions WHERE SUser='".$row['from_user']."'";

				} else {
					if (strlen($row['to_user']) > 18) {
					$user = substr($row['to_user'],0,15) . "...";
					} else {
					$user = $row['to_user'];
					}

					$is_online = "SELECT SID from sessions WHERE SUser='".$row['to_user']."'";
				}

				$SQL->query_db_while($is_online);
				if ($SQL->num_rows_while() == 1) {
				$online = "*";
				} else {
				$online = "";
				}

				if (strlen($row['message']) > 100) {
					$row['message'] = substr($row['message'],0,100) . "...";
				} else {
					$riw['message'] = $row['message'];
				}

				if ($row['viewed'] == "n") {
				$span_id = "new_pm";
				} else {
				$span_id = "text";
				}


				echo "<tr onmouseover=\"this.style.backgroundColor='#F49AC1'\" onmouseout=\"this.style.backgroundColor='#FFFFFF'\">";
				echo "<td width=150 id=text style=\"border-right: 1px solid black;\">&nbsp;<a href=index.php?jump=messages&box=view&id=".$row['PMID']."&old_box=".$_GET['box']." id=".$span_id.">".$user."</a>".$online."</td>";
				echo "<td width=* id=text style=\"border-right: 1px solid black;\">&nbsp ".$row['message']."</td>";
				echo "<td width=100 id=text>&nbsp;";

/*Its this line which is the culprit line.
if i remove it its fine but the date isnt shown.
$ONLINE_USER->PrepareTimestamp() is as above.	
All the arguments are here also if it makes it easier*/				
echo $ONLINE_USER->PrepareTimestamp($row['tdisp_day'],$row['tdisp_month'],$row['tdisp_year']);
					echo "</td>";
					echo "</tr>";


			}

[laserlight]

Ah, that explains it.

I'm not too sure how your database abstraction layer works, but it seems that the database queries within PrepareTimestamp() would affect the database query from the problematic while loop.
So the while loop only executes once before the result set involved no longer exists.

Solving the problem might be a little tricky.
$SQL->fetch_row() must be used, but apparently it only affects the current result set.
Effectively, you're using a DB abstraction layer that restricts you to only working with one result set at a time.
You should either change this, use another DB abstraction layer, or at worst create a new object, e.g. $SQL2
They may be performance problems with the latter in the long run, though.

[pablodelapena]

AH! Im such an idiot!! Thanks for pointing that out to me. For some reason I just didnt see it. I actually have another function for querying within a query. I really should have put two and two together!

Thanks anyway laser. Appreciated.