title: Need help in Php isset()
body: <p>So , I have made a website and its login system . There is a Landing page , a "New post" page and a login page . I do not want the user to access the "New post" page if not logged in [That's solved] , but , if he will try to access it without a session , it will redirect him to the login page with a /login/?new .
  When he logs in with ?new in the address bar , it should redirect him to the "New post" page , if the url is only /login/ , it takes him to the landing .
  That's the code I tried to do :</p>
  
  <pre><code>  if( $count == 1 &amp;&amp; $row['userPass']==$password &amp;&amp; isset($_POST["new"]) )  {
      $_SESSION['user'] = $row['userId'];
      header('Location:../new');
  } else if ($count == 1 &amp;&amp; $row['userPass']==$password) {
      $_SESSION['user'] = $row['userId'];
      header('Location:../');
  }
    else {
      $errMSG = "Incorrect Credentials, Try again...";
  }
  </code></pre>
  
  <p>That's the full code :</p>
  
  <pre><code>&lt;?php
   ob_start();
   session_start();
   require_once 'dbconnect.php';
  
   $error = false;
   if( isset($_POST['btn-login']) ) { 
  
    // prevent sql injections/ clear user invalid inputs
    $email = trim($_POST['email']);
    $email = strip_tags($email);
    $email = htmlspecialchars($email);
  
    $pass = trim($_POST['pass']);
    $pass = strip_tags($pass);
    $pass = htmlspecialchars($pass);
    // prevent sql injections / clear user invalid inputs
  
    if(empty($email)){
     $error = true;
     $emailError = "Please enter your email address.";
    } else if ( !filter_var($email,FILTER_VALIDATE_EMAIL) ) {
     $error = true;
     $emailError = "Please enter valid email address.";
    }
  
    if(empty($pass)){
     $error = true;
     $passError = "Please enter your password.";
    }
  
    // if there's no error, continue to login
    if (!$error) {
  
     $password = hash('sha256', $pass); // password hashing using SHA256
  
     $res=mysql_query("SELECT userId, userName, userPass FROM users WHERE userEmail='$email'");
     $row=mysql_fetch_array($res);
     $count = mysql_num_rows($res); // if uname/pass correct it returns must be 1 row
  
      if( $count == 1 &amp;&amp; $row['userPass']==$password &amp;&amp; isset($_POST["new"]) )  {
          $_SESSION['user'] = $row['userId'];
          header('Location:../new');
  } else if ($count == 1 &amp;&amp; $row['userPass']==$password) {
            $_SESSION['user'] = $row['userId'];
          header('Location:../');
      }
   else {
          $errMSG = "Incorrect Credentials, Try again...";
  }
  
  }
   }
  ?&gt;
  </code></pre>