PAGINATION error >> Undefined variable

[Derokorian]

if (isset($_POST['lab_id']) && is_numeric($_POST['lab_id'])) 
   {         

     $lab_id = $_POST['lab_id']; 
   } 

So if $_POST['lab_id'] isn't set OR its not numeric then it will not be set. So unless your page links are POSTING the lab id, once you past the first page it will not be set.

[vidz]

@

if $la_id isnt set or if it is not numeric how could i get 1st page results?

I think $la_id variable value isnt pass to 2nd,3rd ..... pages thats why Undefined variable error occurred. Therefore i have tried to pass the $la_id value like this

$targetpage = "view_all_chemicallab.php?lab_id={$_REQUEST['lab_id']}";

but it isnt successfull 🙁

[Derokorian]

I like I said, when you first come to the page you are POSTING data, but then you click a link and make a get request, therefore subsequent pages will not see the POSTED data, because its not existent in the request. To do what you're showing in your last response, you'd have to use $_GET to access the value. GET != POST

[vidz]

Thanks Derokorian
My english is bad 🙁. Therefore i didnt get what u have said. can u pls answer this then i will be able to understand 🙂

1. You want me to just change

$targetpage = "view_all_chemicallab.php?lab_id={$_REQUEST['lab_id']}";

to this

$targetpage = "view_all_chemicallab.php?lab_id={$_GET['lab_id']}";

            OR

2. Send values using GET method and do following changes.

   if (isset($_GET['lab_id']) && is_numeric($_GET['lab_id'])) 
      {         
   
        $lab_id = $_GET['lab_id']; 
      }

Any how I have done the both ways but no one works for me same error is still there (IN both methods)

[vidz]

Helpppppppppppppppppppp !!!!!!!

[vidz]

Helppppp !

[cretaceous]

When you submit a form you have the choice to use GET or POST method.

then you access them via
$xyz=$GET['foo_id']
or
$xyz=$POST['foo_id']

In addition you can do
$xyz=$_REQUEST['foo_id']
which will access both GET and POST submissions

GET submissions show in url bar, POST do not

When you go to a page using
echo '<a href="stock_chemical.php?foo=' . $row['bar'] . '">Stock</a>';
then that will be received as a GET submission
it can also be accessed via $_REQUEST

[vidz]

Thanku for ur response cretaceous
but Iam looking something which can make my pagination work.

[cretaceous]

Yes - but it seems you are not able to access 'lab_id' as you need.
And it further appears you are unclear on the usage of GET and POST.
Once you know those you should be able to work out where the problem is.
Echo lab_id to see what it is at each stage

[vidz]

I have added

   echo '<pre>';print_r($_REQUEST);echo '</pre>'; 

line after

 echo $paginate;
	   echo "</div>";

to get an understand about what are posting or geting values
this what i have got in 1st page

Array
(
    [lab_id] => 1
    [page] => 2
    [PHPSESSID] => 86i2ob11e1fg3pib7q8o5cggl2
)

Array
(
    [lab_id] => 1?page=2
    [PHPSESSID] => 86i2ob11e1fg3pib7q8o5cggl2
)

[cretaceous]

try changing this near top of your script:

if (isset($REQUEST['lab_id']) && is_numeric($REQUEST['lab_id']))
{

$lab_id = $_REQUEST['lab_id'];
}

then in script below whenever you want lab_id don't use
$targetpage = "view_all_chemicallab.php?lab_id={$_REQUEST['lab_id']}";
use
$targetpage = "view_all_chemicallab.php?lab_id=".$lab_id;

I'm not sure why your second Request array is showing this :
[lab_id] => 1?page=2

where does that second array come from?
are you using mod _rewrite anywhere?

[Derokorian]

Its because his URL ends up looking like example.com/mypage.php?lab_id=1?page=2 where the second question mark should actually be an ampersand.

[cretaceous]

also if you have a POST AND a GET value with the same name, one will overwrite the other in REQUEST (not sure which way round the overwrite is)

@ - yes but I couldn't see where he gets it to do that..?

[vidz]

@
I have done exactly as u said. BUt it results another error. Now i am having three error massages >>>> Undefined variable: lab_id.

lines which errors belongs to

1.$targetpage = "view_all_chemicallab.php?lab_id=.$lab_id";
2.WHERE lab_inventory_chemical.lab_id= '$lab_id' ";
3WHERE lab_inventory_chemical.lab_id='$lab_id' LIMIT $start, $limit";

[cretaceous]

you mistyped this one - should be :
$targetpage = "view_all_chemicallab.php?lab_id=".$lab_id;

the errors show $lab_id is not set - therefore it's not being passed to your pages correctly

amend upper bit to:
if (isset($REQUEST['lab_id']) && is_numeric($REQUEST['lab_id']))
{
$lab_id = $_REQUEST['lab_id'];
} else {
$lab_id =0;
}
BUT all this will do is set $lab_id to 0 to fix the undefined var error
It won't fix why you are not accessing the id.

[Derokorian]

cretaceous;11006425 wrote:

also if you have a POST AND a GET value with the same name, one will overwrite the other in REQUEST (not sure which way round the overwrite is)

The order is based on php.ini setting: variables_order

@ - yes but I couldn't see where he gets it to do that..?

Its because the change to $targetpage = "view_all_chemicallab.php?lab_id={$_REQUEST['lab_id']}"; and then is building the links using $targetpage?page= so the solution would be to change the links being made to $targetpage&page= so that the query string is constructed properly.

[vidz]

cretaceous;11006430 wrote:

you mistyped this one - should be :
$targetpage = "view_all_chemicallab.php?lab_id=".$lab_id;

No iam not copy paste it once again but same results 🙁 As u said before when it is set to zero in else statement error isnot there how could i find correct solution?

@

Its because the change to $targetpage = "view_all_chemicallab.php?lab_id={$_REQUEST['lab_id']}"; and then is building the links using $targetpage?page= so the solution would be to change the links being made to $targetpage&page= so that the query string is constructed properly.

what i have done according to you

$paginate.= "<a href='$targetpage?page=$next'>next</a>"; 

replace with

$paginate.= "<a href='{$targetpage}&page={$next}'>next</a>"; 

but errors are still there. do i need to change other ? to & ????

[vidz]

I have changed all ? to & but error is still there. can any body tell me am i doing it correctly?

$paginate.= "<a href='{$targetpage}&page={$next}'>next</a>"; 

[vidz]

Helpppppppppppp !

[cretaceous]

a query string should be constructed in this format:

www.mysite.com/page.php?foo=1&bar=99&vxz=berry

the page name is followed by a question mark
any other query string 'name pairs' are separated by ampersands (&)

You need to figure out how to build them correctly!
It's hard to tell what state your script is in now and you need to figure this out for yourself so you understand where to make the changes.