表单文本以指定会话名称

Question

I want to allow the user to input some text, then use that text as their session username and then echo a welcome "username" at the top of each page, and then a logout button which will end the session and allow for the user to input a new username

Currently the code will allow the user to input a name, and then a Welcome will appear for that name, but it will be destroyed if the user changes pages, and the textfield to input a name never disappears either - This is the master page in codeigniter

<form action="" method="POST">
<input type="text" name="input_value">
<input type="submit" name ='in'  value="LogIn">
</form>

<?php
    if (session_status() == PHP_SESSION_NONE) {
      session_start();
        $_SESSION['userses'] = '';
    }

   if(session_status() == PHP_SESSION_ACTIVE && $_SESSION['userses']=='' ){

  $_SESSION['userses'] = $_POST['input_value'];
  echo "Welcome, ".$_SESSION['userses']."!";
   }

 else{
 echo "Welcome, ".$_SESSION['userses']."!";
  }



?>
<form action="<?php session_destroy(); ?>" method="POST">
<input type="submit" name='out' value="LogOff">
</form>

Answer 1

You have to change

if(session_status() == PHP_SESSION_ACTIVE && $_SESSION['userses']=='' )

to

if(isset($_POST['in']) ){

 $_SESSION['userses'] = $_POST['input_value'];
}

so when he submits username, this if will catch the post request and then add input to your username

you don't need to check session_status

edit:

and as the comments said, put session_start(); at the beginning of every page

example of code :

<?php session_start();
if(isset($_SESSION['userses'])) echo "Welcome".$_SESSION['userses']; 
?>
<form action="" method="POST">
<input type="text" name="input_value">
<input type="submit" name ='in'  value="LogIn">
</form>

<?php

if(isset($_POST['in']) ){

 $_SESSION['userses'] = $_POST['input_value'];
}
?>
<form action="<?php session_destroy(); ?>" method="POST">
<input type="submit" name='out' value="LogOff">
</form>

You are using codeigniter, why not use session library :

https://www.codeigniter.com/user_guide/libraries/sessions.html