New with Code Igniter - Application structure

[eluser]TheFuzzy0ne[/eluser]
It's a question of scope. $data is available within the confines of the function it's declared in, if you declare $data as a class variable, it's available to the whole class, and accessed via $this->data. $this->something means you want to access a variable that's in the global scope of the current object. $this won't work outside of an object.

Code:

class Example {

    var $data = 'Class data';

    function getData($from_class=FALSE)
    {
        $data = "Function data";        

        if ($from_class === TRUE)
        {
            return $this->data; # returns the class variable
        }
        else
        {
            return $data; # returns the function variable.
        }
    }
}

$example = new Example();

echo $example->getData() . "\n"; # Echoes "Function data"
echo $example->getData(TRUE) . "\n"; # Echoes "Class data"

The above code is untested.

I hope this helps without causing more confusion.