form help

lorddraco98

here's my code

<?php
if ($_GET['action']=="" || !isset($_GET['action']))
{
	echo "<form method='post' action='test.php?action=go'>";
	$a=3;
	for ($i=1; $i<=$a;$i++)
	{
	echo "<input type='text' name='testvar[$i]'><br>";
	}
echo "<input type='submit'>";
echo "</form>";
}
if ($_GET['action']=="go")
{
	$a=3;
	for ($i=1; $i<=$a; $i++)
	{
		echo $_POST['testvar'][$i]."<br>";
	}
echo "<form method='post' action='test.php?action=go2'>";
for ($i=1; $i<=$a;$i++)
{
echo "<input type='hidden' name='testvar[$i]' value='$_POST[testvar][$i]'>";
}
echo "<input type='submit'>";
echo "</form>";
}
if ($_GET['action']=="go2")
{
	$a=3;
	for ($i=1; $i<=$a; $i++)
	{
		echo $_POST['testvar'][$i]."<br>";
	}
}
?>

now, on the last page(test.php?action=go2), if I typed in 1,2, and 3 successivly on the input boxes, shouldn't it echo "1, 2,3"?

it doesn't though, it echos:
Array[1]
Array[2]
Array[3]

what am I doing wrong?

matt_4013

Your problem is this line 🙂

echo "<input type='hidden' name='testvar[$i]' value='$_POST[testvar][$i]'>";

Change it to:

echo "<input type='hidden' name='testvar[$i]' value='".$_POST['testvar'][$i]."'>";

Probably the easiest way to avoid stuff like this is to not take shortcuts. You put in an extra 6 characters, it makes it a lot easier to read, and it works 🙂

Hope that helps,
Matt

lorddraco98

that works, thanks.
tell me something, can you explain why that works and mine doesn't hehe

i kinda understand the quotes, but i'm not understanding what the periods do.
thanks!

Weedpacket

The . is just the bog-standard string concatenation operator.

Your code wasn't working, because PHP was wrong about where the variable name ended and the rest of the text began. It though the variable was $POST['testvar'] and echoed that (when you echo an array it comes out as "Array"). It didn't realise that it was supposed to go on and read $POST['testvar'][0] as the variable!

Taking the variable out of the string and using string concatenation leaves no doubt as to which bits are text and which bits are variables.

lorddraco98

Originally posted by Weedpacket
The . is just the bog-standard string concatenation operator.

Your code wasn't working, because PHP was wrong about where the variable name ended and the rest of the text began. It though the variable was $POST['testvar'] and echoed that (when you echo an array it comes out as "Array"). It didn't realise that it was supposed to go on and read $POST['testvar'][0] as the variable!

Taking the variable out of the string and using string concatenation leaves no doubt as to which bits are text and which bits are variables.

interesting, thank you!
Never came across a situation like that before, so that's why it stumped me hehe

Weedpacket

Originally posted by lorddraco98
interesting, thank you!
Never came across a situation like that before, so that's why it stumped me hehe

It's a little bit inconsistent, in my opinion; if it's going to stop before the second array index, why not stop before the first? And if it's going to read the first, why not the second?

One can get around this by wrapping potentially confusing variables in {}, but taking them out of the string the way matt_4013 suggests is likely the better approach in general.