Question about isset($_session['username'])

Question

I have a login page when clicked on defines the variable $_session[username] = $name; this $_session['username'] is displayed on my main page and it works fine if someone does login. however when someone does not login, the error notice:undefined index pops up. if i use

<?php session_start(); if($_SESSION['username']==""|| isset($_SESSION['username'])){echo "Login";}else{echo "Logout";}?>

i thought it would fix the problem. but it has the same error

Your if statement needs to check if the field exists before testing it. — Nigel Ren, Feb 12 '20 at 15:20
_..did not seem to work.._ Was session username set before you tested? — B001ᛦ, Feb 12 '20 at 15:21
@NigelRen how do i check if the field exists? sorry very new to php — Noiderate ana, Feb 12 '20 at 15:23

score 0 · Accepted Answer · answered Feb 12 '20 at 15:21

0

if $_SESSION['username] is not set, you'll receive an undefined error message.

I'd recommend using empty(). It's the same thing as saying if( isset($_SESSION['username']) && $_SESSION['username] != '' ). This is more resource intensive (minimally in your case), as it has to check if the variable isset and that it isn't empty (blank, false, 0, null, etc).

if( empty($_SESSION['username']) ){
    echo 'Login';
}else{
    echo 'Logout';
}

answered Feb 12 '20 at 15:21

Samuel Cook

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i have gone through a couple of other posts and saw this too. however it did not fix the issue. the same error pops up again saying undefined index: username – Noiderate ana Feb 12 '20 at 15:26

Question about isset($_session['username'])

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