[RESOLVED] class not working

[scrupul0us]

im trying my hand at building some date class stuff... im having issues with the class extender:

<?php
class dt
{
	var $dtNow;
	var $dtOther;

function dt()
{
	$this->dtNow = strtotime('now');
	$this->dtOther = strtotime('now');
}	
function difference()
{
	return $this->dtOther - $this->dtNow;
}
}

class dt_distance extends dt
{
	var $years;
	var $months;
	var $weeks;
	var $days;
	var $hours;
	var $minutes;
	var $seconds;
	var $tence;	
	var $diff;
	var $debug;

var $cyears = 31536000;
var $cmonths = 2628000;
var $cweeks = 604800;
var $cdays = 86400;
var $chours = 3600;
var $cminutes = 60;
var $cseconds = 1;

function dt_distance()
{
	parent::dt();
	$this->years = 0;
	$this->months = 0;
	$this->weeks = 0;
	$this->days = 0;
	$this->hours = 0;
	$this->minutes = 0;
	$this->seconds = 0;
	$this->tence = '';
	$this->diff = dt::difference();
}

function distance()
{
	//YEARS
	if ($this->diff/$this->cyears > 1)
	{
		$this->debug = "years";
		$this->years = (int) $this->diff/$this->cyears;
		$this->diff = $this->diff - ($this->years * $this->cyears);
	}
	//MONTHS
	if ($this->diff/$this->cmonths > 1)
	{
		$this->debug = "months";
		$this->months = (int) $this->diff/$this->cmonths;
		$this->diff = $this->diff - ($this->months * $this->cmonths);
	}
	//WEEKS
	if ($this->diff/$this->cweeks > 1)
	{
		$this->debug = "weeks";
		$this->weeks = (int) $this->diff/$this->cweeks;
		$this->diff = $this->diff - ($this->weeks * $this->cweeks);
	}
	//DAYS
	if ($this->diff/$this->cdays > 1)
	{
		$this->debug = "days";
		$this->days = (int) $this->diff/$this->cdays;
		$this->diff = $this->diff - ($this->days * $this->cdays);
	}
	//HOURS
	if ($this->diff/$this->chours > 1)
	{
		$this->debug = "hours";
		$this->hours = (int) $this->diff/$this->chours;
		$this->diff = $this->diff - ($this->hours * $this->chours);
	}
	//MINUTES
	if ($this->diff/$this->cminutes > 1)
	{
		$this->debug = "minutes";
		$this->minutes = (int) $this->diff/$this->cminutes;
		$this->diff = $this->diff - ($this->minutes * $this->cminutes);
	}
	//SECONDS
	if ($this->diff/$this->cseconds > 1)
	{
		$this->debug = "seconds";
		$this->seconds = (int) $this->diff/$this->cseconds;
		$this->diff = $this->diff - ($this->seconds * $this->cseconds);
	}
}			
}

$dt = NEW dt_distance;
$dt->dtNow	 = strtotime('now');
$dt->dtOther = strtotime('now +5 day');
echo "diff: ".$dt->difference()."<br>";
echo "dt->diff: ".$dt->diff."<br>";
$dt->distance();
echo "Debug: ".$dt->debug."<br>";
echo "Seconds: ".$dt->seconds."<br>";

my output is:

diff: 432000
dt->diff: 0
Debug:
Seconds: 0

for some reason the extended class isnt reading the difference calculated in the base class

any ideas?

[scrupul0us]

bump...

[NogDog]

Looks like the problem is that when you call the difference() method, all it does is return the difference, but it's not saved anywhere. Either add the $diff variable to the parent class and have the method set its value, or else overwrite the method in the child class to do it there, e.g.:

class dt_distance extends dt
{
    // . . . //

function difference()
{
    $this->diff = parent::difference();
    return $this->diff;
}
}

PS: in your test, since you are adding exactly 5 days, seconds will still be zero, but the days variable does get set to 5.

[scrupul0us]

thanks nog!

[NogDog]

scrupul0us;10885179 wrote:

thanks nog!

That should work, too. (BTW: In my previous example, there should be no need to call the parent, since the difference method should be inherited.)

[scrupul0us]

yea thats my next question... this works however i have to call the difference:

<?php
class dt
{
	var $dtNow;
	var $dtOther;

function dt()
{
	$this->dtNow = strtotime('now');
	$this->dtOther = strtotime('now');
}	
function difference()
{
	return $this->dtOther - $this->dtNow;
}
}

class dt_distance extends dt
{
	var $years;
	var $months;
	var $weeks;
	var $days;
	var $hours;
	var $minutes;
	var $seconds;
	var $tence;	
	var $diff;
	var $debug;

var $cyears = 31536000;
var $cmonths = 2628000;
var $cweeks = 604800;
var $cdays = 86400;
var $chours = 3600;
var $cminutes = 60;
var $cseconds = 1;

function dt_distance()
{
	parent::dt();
	$this->years = 0;
	$this->months = 0;
	$this->weeks = 0;
	$this->days = 0;
	$this->hours = 0;
	$this->minutes = 0;
	$this->seconds = 0;
	$this->tence = '';
	//$this->diff = $this->difference();
}
function difference()
{
	$this->diff = parent::difference();
	return $this->diff;
} 
function distance()
{
	//YEARS
	if ($this->diff/$this->cyears > 1)
	{
		$this->debug = "years";
		$this->years = (int) $this->diff/$this->cyears;
		$this->diff = $this->diff - ($this->years * $this->cyears);
	}
	//MONTHS
	if ($this->diff/$this->cmonths > 1)
	{
		$this->debug = "months";
		$this->months = (int) $this->diff/$this->cmonths;
		$this->diff = $this->diff - ($this->months * $this->cmonths);
	}
	//WEEKS
	if ($this->diff/$this->cweeks > 1)
	{
		$this->debug = "weeks";
		$this->weeks = (int) $this->diff/$this->cweeks;
		$this->diff = $this->diff - ($this->weeks * $this->cweeks);
	}
	//DAYS
	if ($this->diff/$this->cdays > 1)
	{
		$this->debug = "days";
		$this->days = (int) $this->diff/$this->cdays;
		$this->diff = $this->diff - ($this->days * $this->cdays);
	}
	//HOURS
	if ($this->diff/$this->chours > 1)
	{
		$this->debug = "hours";
		$this->hours = (int) $this->diff/$this->chours;
		$this->diff = $this->diff - ($this->hours * $this->chours);
	}
	//MINUTES
	if ($this->diff/$this->cminutes > 1)
	{
		$this->debug = "minutes";
		$this->minutes = (int) $this->diff/$this->cminutes;
		$this->diff = $this->diff - ($this->minutes * $this->cminutes);
	}
	//SECONDS
	if ($this->diff/$this->cseconds > 1)
	{
		$this->debug = "seconds";
		$this->seconds = (int) $this->diff/$this->cseconds;
		$this->diff = $this->diff - ($this->seconds * $this->cseconds);
	}
}			
}

$dt = NEW dt_distance;
$dt->dtNow	 = strtotime('now');
$dt->dtOther = strtotime('now +5 day');
$dt->difference();
$dt->distance();
echo "Debug: ".$dt->debug."<br>";
echo "Years: ".$dt->years."<br>";
echo "Months: ".$dt->months."<br>";
echo "Weeks: ".$dt->weeks."<br>";
echo "Days: ".$dt->days."<br>";
echo "Hours: ".$dt->hours."<br>";
echo "Minutes: ".$dt->minutes."<br>";
echo "Seconds: ".$dt->seconds."<br>";

is there anyway such that when i create a new instance of dt_distance it runs difference and distance for me?

[scrupul0us]

did some consolidation and reworking... it all works but i still have to initiate the difference() function manually after creating a new instance of the class... is there anyway to automate that?

<?php
class dt
{
	/*
	Class:      	dt
	Extends: 	<none>
	*/

//VARIABLES
var $dateNow;
var $dateOther;
var $tence;
var $diff;

var $years;
var $months;
var $weeks;
var $days;
var $hours;
var $minutes;
var $seconds;	

//CONSTANTS
const cyears 	= 31536000;
const cmonths 	= 2628000;
const cweeks 	= 604800;
const cdays 	= 86400;
const chours 	= 3600;
const cminutes = 60;
const cseconds = 1;

function __CONSTRUCT()
{
	$this->dateNow 		= strtotime('now');
	$this->dateOther 	= strtotime('now');
	$this->years 		= 0;
	$this->months 		= 0;
	$this->weeks 		= 0;
	$this->days 		= 0;
	$this->hours 		= 0;
	$this->minutes 		= 0;
	$this->seconds 		= 0;
	$this->tence 		= '';
}
function difference()
{
	$this->diff = $this->dateOther - $this->dateNow;
	if($this->diff < 0) { $this->tence = 'Ago'; }
	if($this->diff > 0) { $this->tence = 'Left'; }
} 
function distance()
{		
	if ($this->diff/dt::cyears >= 1)
	{
		$this->years = floor($this->diff/dt::cyears);
		$this->diff -= ($this->years * dt::cyears);
	}		
	if ($this->diff/dt::cmonths >= 1)
	{
		$this->months = floor($this->diff/dt::cmonths);
		$this->diff -= ($this->months * dt::cmonths);
	}
	if ($this->diff/dt::cweeks >= 1)
	{
		$this->weeks = floor($this->diff/dt::cweeks);
		$this->diff -= ($this->weeks * dt::cweeks);
	}
	if ($this->diff/dt::cdays >= 1)
	{
		$this->days = floor($this->diff/dt::cdays);
		$this->diff -= ($this->days * dt::cdays);
	}
	if ($this->diff/dt::chours >= 1)
	{
		$this->hours = floor($this->diff/dt::chours);
		$this->diff -= ($this->hours * dt::chours);
	}
	if ($this->diff/dt::cminutes >= 1)
	{
		$this->minutes = floor($this->diff/dt::cminutes);
		$this->diff -= ($this->minutes * dt::cminutes);
	}
	if ($this->diff/dt::cseconds >= 1)
	{
		$this->seconds = floor($this->diff/dt::cseconds);
		$this->diff -= ($this->seconds * dt::cseconds);
	}
}
function convert()
{
	$this->years 	= floor($this->diff/dt::cyears);
	$this->months 	= floor($this->diff/dt::cmonths);
	$this->weeks 	= floor($this->diff/dt::cweeks);
	$this->days 	= floor($this->diff/dt::cdays);
	$this->hours 	= floor($this->diff/dt::chours);
	$this->minutes 	= floor($this->diff/dt::cminutes);
	$this->seconds 	= floor($this->diff/dt::cseconds);
}	
}
?>

[NogDog]

You can call $this->difference() from the constructor, if that's what you mean?

Another thought, just for ease of use, you could add an optional arg to the constructor for the "other" time, and if it is set then assign it. In fact, I might structure it something like:

<?php
class dt
{
   protected $dtOther;
   // other vars...

   public function __construct($date = null)
   {
      if($date !== null)
      {
         if($this->setDate($date) === false)
         {
            throw new Exception(__method__ . "(): Could not set date '$date'");
         }
      }
   }

   public function setDate($date)
   {
      if('<whatever validation you want for $date>' === false)
      {
         user_error(__method__ . "()): invalid date '$date'");
         return false;
      }
      $this->dtOther = $date;
      return $this->difference();
   }

   function difference()
   {
      $this->diff = $this->dateOther - $this->dateNow;
      if($this->diff < 0)
      {
         $this->tence = 'Ago';
      }
      if($this->diff > 0)
      {
         $this->tence = 'Left';
      }
      return true;
   }

   // other methods...
}

[scrupul0us]

now perhaps this isnt the best place to ask however whats the difference between private and public functions and protected vars etc... I tried to grasp some concepts from the php manual but its rather unclear to me and not well put together all the things one might see in OOP

e.g.
private/public
method
Exception
etc...

is there any good resource that really gives a good overview of PHP OOP and the variable methods/operators etc, that one might use/find within PHP OOP

for the first time ever i sort of feel comfortable, or at least, a lot more comfortable with OOP just in writing this, which i consider to be my first real working class... I however recognize that it doesnt even scratch the surface of whats available/capable for OOP... i hope that makes sense....

[NogDog]

Private things (functions or variables) can only be accessed from within the class and are not inherited by child classes.

Protected things are like private things, except they are inherited by the class's children.

Public things are accessible from the client code (not "client" as in "client/server" but as in the code that instantiates the class), and they are inherited.

Probably the one thing that did the most to start making things click for me with OOP (though believe me I still have a lot to learn) is Matt Zandstra's book PHP 5 Objects, Patterns, and Practice (I believe a 2nd edition was released this year, so you should look for that if you want to buy it). He has a few PHP OOP tutorials floating around on the web that you might want to search for, too.

[scrupul0us]

excellent as usual... I really appreciate the help and advise... thanks alot