how to change login button to logout after the user login PHP-CodePudding

My login button maintains login after the user logged in. The code below is what I tried.

<?php 
        //session_start();
        if (isset($_SESSION['user_logged_in'])) {
            echo' <a href="logout.php"><input id="btnlogout" 
type="button" value="LOGOUT"  /></a>';
        } else {
            echo '<a href="login.php"><input id="btnlogin" 
type="button" value="LOGIN"  /></a>';
            echo '<a href="register.php"><input id="btnregistser" 
type="button" value="Register"  /></a>';
        }
        ?>

logout.php

<?php
session_start();
unset($_SESSION['user_logged_in']);
session_destroy();
echo "You have logout successfully";
header("refresh:2;url=homepage.php");
?>

check.php (to check on homepage 1st php data)

if ($username==$row['username'] && $password==$row['password']){
        session_start();
        //$_SESSION['username']=$username;
        $_SESSION['user_logged_in'] = true;
    echo "You have logged in successfully.";
    header("refresh:2;url=homepage.php");
    break;
    }
    else{   
        session_start();
        $_SESSION['username']=$username;
    header("Location:fail.php");
    }
        }

I expect the button can change to logout button but it doesn't work.

CodePudding user response：

It should look something like this

<?php 
//session_start();
if (isset($_SESSION['user_logged_in'])) {
    echo' <a href="logout.php"><input id="btnlogout" type="button" value="LOGOUT"  /></a>';
} else {
    echo '<a href="login.php"><input id="btnlogin" type="button" value="LOGIN"  /></a>';
    echo '<a href="register.php"><input id="btnregistser" type="button" value="Register"  /></a>';
}
?>