require_once has failed to include the template file. Why? - php

Question

The following code is showing the following error:
Warning: require_once(/home/..../public_html/edu) [function.require-once]: failed to open stream: Success in /home/..../public_html/edu/index.php on line 25
Fatal error: require_once() [function.require]: Failed opening required '' (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/..../public_html/edu/index.php on line 25
How can I solve this problem?
<?php
class Model
{
public $tstring;
public function __construct(){
$this->tstring = "The string has been loaded through the template.";
$this->template = "tpl/template.php";
}
}
class View
{
private $model;
public function __construct($model) {
$this->controller = $controller;
$this->model = $model;
}
public function output(){
$data = "<p>" . $this->model->tstring ."</p>";
require_once($this->model->template); //line 25 Attention!!!!!!!!
}
}
class Controller
{
private $model;
public function __construct($model){
$this->model = $model;
}
public function clicked() {
$this->model->string = "Updated Data, thanks to MVC and PHP!";
}
}
$model = new Model();
$controller = new Controller($model);
$view = new View($controller, $model);
echo $view->output();

Answer 1

I find things are greatly simplified when you use relative or absolute/relative paths - so you get to the file you're requiring via the file that requires it, instead of the root directory.
For instance, let's say you have a setup like this:
--/
|
| --var
|
|--www
|
|--html
|
|--index.php
|
|--includes
|
|--util.php
A client runs the index.php file. Let's say that index.php needs to include util.php are three ways to do this (the following lines would exist in index.php)
Absolute:
require_once('/var/www/html/includes/util.php');
Relative:
require_once('./includes/util.php');
Absolute/Relative:
require_once(dirname(__FILE__).'/includes/util.php');
As you can see, the absolute method addresses the util.php file starting from the / directory. The relative method addresses util.php by starting from index.php, and supplying the path that gets from index.php to util.php. The absolute/relative method actually RESOLVES to the absolute method because the string dirname(__FILE__).'/includes/util.php' will actually resolve to "/var/www/html/includes/util.php", but the functionality still appears as relative because you only need to think about the path that gets from index.php to util.php.
I tend to prefer the absolute/relative approach.
Instead of $this->template = "tpl/template.php" you may want to try
$this->template = dirname(__FILE__).'/tpl/template.php';
Even if you still have a problem at this point, you can echo your $this->template variable in order to see exactly what file you are addressing.
Confused about the dirname(__FILE__) part? Here are some links.
dirname
http://ca1.php.net/dirname
__FILE__
http://us2.php.net/manual/en/language.constants.predefined.php
Hope this helps and good luck!