Comments on: PHP & MySQL Tutorial 08: Mysql Login system concept

By: PHP Tutorials By Kloplop321 » Blog Archive » PHP & MySQL Tutorial 12: Logging into a Basic Blog

Sun, 04 Jul 2010 04:17:56 +0000

[...] future tools for the blog administration that will be shown in future tutorials. You may refer to Tutorial 8(Login Concept) as we go though this [...]

By: Sivaeb

Sivaeb — Thu, 03 Jun 2010 15:46:03 +0000

Yes it clear it up thanks

By: Kloplop321

Kloplop321 — Thu, 03 Jun 2010 15:30:50 +0000

This usually happens when you have a variable in the SESSION that doesn’t exist right now
So like $_SESSION['username'], the username variable obviously will not be available when the user is not logged in. So, in order to address this issue,
you do
if(isset($_SESSION['username'])){
//do code here
}
this checks to see if the variable exists(is set) then you are safe to access it. This is only a notice, so it doesn’t matter much in the long run.
The reason why you are seeing notices is because in your php.ini (php settings file) the error reporting is most likely set to E_ALL, you can change it to E_ERROR and just have a filter so you don’t see the notices. I have the error reporting so it doesn’t show these notices.

As you can see by my tutorial, I am only seeing if the session variable, isin, is set to 1.
if($_SESSION['isin'] == 1){
Now, if the variable does not exist(undefined index, meaning isin doesn’t exist), then it will return false for that variable.
The computer now sees it as
if(false == 1)
logically false is 0, and 0 is not 1, so it does not execute the code that should happen when ‘isin’ is set to true or 1.

Does that help your understanding?

By: Sivaeb

Sivaeb — Thu, 03 Jun 2010 14:51:17 +0000

It seems to be when I log out or are not logged in.

By: Sivaeb

Sivaeb — Thu, 03 Jun 2010 14:36:01 +0000

For some reason I keep getting an Error…
Notice: Undefined index: isin in C:\wamp\www\neighborhoodbusinessguide\index.php on line 30

By: Kloplop321

Kloplop321 — Fri, 28 May 2010 18:33:48 +0000

I am sorry about that. I learned from that, thanks to commentators like you from youtube. I have been trying to minimize all distractions like that as I have been working on my future tutorials.

By: John

John — Fri, 28 May 2010 18:21:11 +0000

This tutorial was extremely distracting and ultimately useless. I’m sure the information is good enough, but your windows are transparent, your background changes every minute, and the camera follows the mouse around while we’re attempting to read your code… this was completely unwatchable.

By: Haley Schillig

Haley Schillig — Tue, 27 Apr 2010 21:37:20 +0000

I’m currently still in the making of a website.
When will you post the registering part?
Out of everyones, your tutorials are the only ones that work and I WOULD LOVE to see the registering part.
Your tutorials are so easier to understand and very organized.
And I think the login system is the hardest part because it’s what your whole site is about..
Please email me back and let me know if you are going to make a tutorial for the registering part (:
I sure hope you are still giving out tutorials. Thanks so much<3

By: Charles

Charles — Tue, 16 Mar 2010 01:55:27 +0000

Very nice tutorial!