PHP content of session variable -

i'm trying pass value between 2 pages through $_session variable empty follows:

i'm assigning session variable value on 1 php page:

$_session["elementname"]="a_373"; 

and trying store in variable on page follows:

if (!empty($_session["elementname"])) {     $elemname=$_session["elementname"];     $_session["elementname"]=""; } else {     $elemname=""; } 

the value of $elemname empty when print out. however, correct printout when remove $_session["elementname"]=""; line above code.

edit: i'm printing $elemname , not $_session["elementname"] - print($elemname);

i'm on shared hosting account php 5.3.2 , register_globals set off (as per phpinfo();).

i need reset/empty session variable once value has, it's not working , has been baffling me last couple of days. ideas why? thanks!

edit:

additional clues: tested session's var_dump before if statement , set value $elemname in else section follows:

var_dump($_session["elementname"]);  $elemname="x";  if (isset($_session["elementname"]) && !empty($_session["elementname"])) {     $elemname=$_session["elementname"];     $_session["elementname"]=""; } else {     $elemname="none"; }  print("<br />".$elemname); 

i got result:

string(5) "a_373" none 

try using isset($_session["elementname"]) , unset($_session["elementname"]) instead.