How can I prevent access to my view if there's not an article with that ID in CodeIgniter?

Question

Hi. I'm developing a web app on CodeIgniter.
When the users want to view an article on my website, they will go to a URL like articles/view/2 . Now I just found out that if someone just randomly passes in a number like 255 it won't go to 404 and it will show an error instead. How can I fix this? How can I say, if it's not a valid article ID, redirect them or smth like that? Thanks in advance.

miguelcastro2 · Accepted Answer

The issue here is that you have a URL that uses a primary key to retrieve a record from the database. If the record does not exist, your app crashes. You always need to check to see if the database successfully retrieved a record. You need to add code to check whether your model was able to retrieve a record and if not, use CodeIgniters show_error() (https://ellislab.com/codeigniter/user-guide/general/errors.html) function to display an error. Below is a pseudo code sample:
```Php
<?php // Get ID from URL
$id = 255;
if ($this->myModel->find($id)) {
    // Load Views
} else {
   show_error("Error: could not locate articles.");
}
?>
```
A Better way would be to use PHP exceptions (http://php.net/manual/en/language.exceptions.php) to generate an exception when a record is not found and use try/catch to respond to the exception. 
The overall idea is that as a developer you need to make sure your program is prepared to handle different scenarios, especially the ones where you do not receive the input you were expecting.

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Arash Emadi

Arash Emadi

How can I prevent access to my view if there's not an article with that ID in CodeIgniter?

1 Answer

miguelcastro2

miguelcastro2