Answers for "php session lost value"

php unset session variable

// Destroy a sesion variable name 'variable_name' 
<?php
unset($_SESSION['variable_name']);
?>

php session get data

<?php
  session_start();  
  if(isset($_SESSION['views']))
      $_SESSION['views'] = $_SESSION['views']+ 1;
  else
      $_SESSION['views'] = 1;

  echo "views = " . $_SESSION['views']; 
?>