Variable is no longer assigned after the first if statement

[rotcjackhammer]

Hello all, first I have been searching for a resolution for this problem for days, stackoverflow and various other google searches don't seem to address the issue I'm having without something else being added into the scenario that's different from my experience.

 

What I am doing is passing a primary key to another php page to edit my database using an UPDATE sql statement. First, the variable is transferred using $_GET and is visible in the isset($_GET['id']) if statement to select all corresponding IDs that match and place the database content into HTML text boxes for editing. This phase of the program works fine, but the ID variable is not accessible outside the isset($_GET[]) if statement so I can then use is in the isset($_POST) if statement which of course has the UPDATE sql statement.

 

The code is attached.

 

phpfreaks.php

[Jacques1]

The POST parameter is called course, but you're trying to fetch course_id. Whenever you have trouble with form parameters, it's a good idea to actually inspect them:

var_dump($_POST);

This quickly reveals all misunderstandings, typos etc.

 

But more importantly, your code is full of security vulnerabilities. You sometimes apply SQL-escaping (based on your current mood rather than technical criteria, I guess), but most of the time, you just dump the user input straight into your queries and HTML markup. This leaves you wide open to SQL injection attacks, cross-site scripting, cross-site request forgery and whatnot.

 

Learning how to use mysqli properly is unrealistic in my experience, so I suggest you switch to PDO. Then you'll need to learn the basics of safe programming (as opposed to: let's write some code and hope nobody will bother to break it).

Edited December 11, 2016 by Jacques1

[rotcjackhammer]

Thanks for the feedback. It's most graciously accepted. Sometimes when you stare at something so long it all begins to run together, so a fresh set of eyes is good sometimes.

 

I'm far from being a competent PHP programmer, I'm still learning the nuances, let alone the complexities.

 

Thanks again, Guru!