[RESOLVED] OOP - variables losing values

[sakurachan]

Firstly Apologies, this is a pain in the ass to decribe and plus it's my first OOP app. so if I miss some fundamental mistake I'm sorry.

I'll give you the basic info and then I'll describe my problem.

Database:

user_table

userID -> int
userFname -> nvarhcar
userLname -> nvarhcar
userAddress -> int (relation to adderID in addr_table)
userAge -> int

---

addr_table

addrID -> int
addrStreetNum -> int
addrStreet -> nvarchar
addrSuburb -> nvarchar
addrState -> nvarchar
addrCountry -> nvarchar

addrPCode -> nvarchar

PHP Classes

class ConnectionDB {

public 		$storedProcedures = array();
private 	$db_server;
private 	$db_user;
private 	$db_password;
private 	$db;

function __construct() {

	$db_server = "xxxxxx";
	$db_user = "xxxxxx";
	$db_password = "xxxxxx";
	$db = "xxxxxx";

	$db_connection 	= mssql_connect($db_server, $db_user, $db_password);
	$db_select = mssql_select_db($db);

	include_once("project.dbSettings");
	$this->storedProcedures = $storedProcedures;
}

    function buildSQL ($tSP, $tData) {

	$myEval = '$query = mssql_init("'.$this->storedProcedures[$tSP]['name'].'");' . "\r\n";
	$tData = array_values($tData);

	$i = 0;

	foreach($this->storedProcedures[$tSP]['arguments'] as $item) {
		$myEval .= '$str_'.$i.' = "' . $tData[$i]['Value'] . '";' . "\r\n";
		$myEval .= 'mssql_bind($query, "@' . $item . '", &$str_' . $i . ', ' . $this->getDataType($tData[$i]['Name']) . ');' . "\r\n";
		$i ++;
	}
	return $myEval;
}

    function execSQL ($tSQL) {
	$this->db_connection;
	$this->db_select;

	eval($tSQL);

	$result = mssql_execute($query) or die($tSQL);
	$num_fields = mssql_num_fields($result);

	$x = 0;

	while( $row = mssql_fetch_array($result) ) {
		for( $j=0; $j<$num_fields; $j++ ) {
			$name = mssql_field_name($result, $j);
			$object[$x][$name] = $row[$name];
		}
		$x ++;
	}

	if (!isset($object)) {
		$object = Array( "FALSE" );
	}
	mssql_close();

	return $object;
}	
}

An example of the project.dbSettings file:

$storedProcedures = array	(
"skdcinonqmndc" => array ("name" => "test_connection",						
"description" 	=> "tests the connection to the database",	"arguments" 	=> array()) 
)

System class

class System {

function __construct () {}
function returnUserDetails($userID) {

		$myConnection = new ConnectionDB;

		$myData = array();
		$myData['UID']['Value'] = $PocID;
		$myData['UID']['Name'] = "txt-01";

		$sp = "04jfk2jsd92";

		$mySQL = $myConnection->buildSQL($sp, $myData);
		$myResult = $myConnection->execSQL($mySQL);

    return ($myResult);
}

function returnAddrDetails($addrID) {
  $myConnection = new ConnectionDB;

    $myData = array();
    $myData['AddrID']['Value'] = $addrID;
    $myData['AddrID']['Name'] = "txt-01";

    $sp = "94f92jek2";

    $mySQL = $myConnection->buildSQL($sp, $myData);
    $myResult = $myConnection->execSQL($mySQL);

  return ($myResult);   
}

User Class:

include("System.class.php");
include("Address.class.php");

class User {
    public $Fname;
    public $Lname;
    public $objAddr;
    public $Age;
    public $id;

function __construct($uid) {
   $this->id = $uid;

   $mySystem = new System;

   $arr_UserDetails = $mySystem->returnUserDetails($this->id);
   $this->Fname = $arr_UserDetails[0]['userFname'];
   $this->Lname = $arr_UserDetails[0]['userLName'];

   $this->objAddr =  new Address($arr_UserDetails[0]['userAddress ']);

   $this->Age = $arr_UserDetails[0]['userAge'];


}
}

Address Class:

include_once("System.class.php");

class Address {

public $StreetNum;
public $Street;
public $Suburb;
public $State;
public $Country;
public $PCode;

function __construct ($addrID) {
	$this->id = $addrID;

	$mySystem = new System;
	$arr_AddrDetails = $mySystem->returnAddrDetails($this->id);

	$this->StreetNum 	= $arr_AddrDetails[0]['addrStreetNum'];
	$this->Street 				= $arr_AddrDetails[0]['addrStreet'];
	$this->Suburb			 	= $arr_AddrDetails[0]['addrSuburb'];
	$this->State					= $arr_AddrDetails[0]['addrState'];
	$this->Country			= $arr_AddrDetails[0]['addrCountry'];
	$this->PCode				= $arr_AddrDetails[0]['addrPCode'];

}

}

This idea behind this is that I'm hoping to be able access a users address information by doing the following:
$user = new User("1");
$country = $user->objAddr->country;

or at least something like that.

My problem though with the $this->storedProcedures variable in the Connection.class.php file.

With the first instance of the Connection class it's value is the entire contents of the $storedProcedures array in project.dbSettings, on the second subsequent
instance it loses the entire content of the array, it's type is still type array, but it is empty. Very very strange.

I know it's a headache reading through all this, if I'm doing something silly and newbie esque I am sorry, and I appreciate any help I can get.

Thanks.
S

[drew010]

quick question, from reading the following paragraph

"With the first instance of the Connection class it's value is the entire contents of the $storedProcedures array in project.dbSettings, on the second subsequent
instance it loses the entire content of the array, it's type is still type array, but it is empty. Very very strange. "

do you mean that when you load the page the first time, the $storedProcedures array gets stored. then when you load the page a second time its gone?

if so, this is normal. all data in the class is destroyed after the script ends.

if i misunderstood and thats way off, sorry

[sakurachan]

Hey thanks, it's almost right but I'll detail it better

(1) class User {
(2)    public $Fname;
(3)    public $Lname;
(4)    public $objAddr;
(5)    public $Age;
(6)    public $id;

(7)    function __construct($uid) {
(8)       $this->id = $uid;
(9)
(10)       $mySystem = new System;
(11)
(12)       $arr_UserDetails = $mySystem->returnUserDetails($this->id);
(13)       $this->Fname = $arr_UserDetails[0]['userFname'];
(14)       $this->Lname = $arr_UserDetails[0]['userLName'];
(15)       

(16)       $this->objAddr =  new Address($arr_UserDetails[0]['userAddress ']);
(17)
(18)       $this->Age = $arr_UserDetails[0]['userAge'];
(19)
(20)
(21)    }
(22)}

first instance of Connection class is on line 12, where the system::returnUserDetails is clalled.

second instance of Connection class is on line 16, where the address object is created, the real instance occurs in the following line in Address.class;

$arr_AddrDetails = $mySystem->returnAddrDetails($this->id);

Essentially I can't get anything from the database because if can't find the stored procedure reference from the $this->storedProcedure has lost it's value on the second instance.

[Shrike]

At a guess it's because you use include_once() inside of the constructor, and so the file is not included on subsequent object creation. Might be better including the file outside of the class entirely and pass $storedProcedures as a parameter when creating each object.

[sakurachan]

you gave me a hint in your

include_once

reference, what if I just pass the project.dbSettings file to an

include

function inside the constructor

ie:

function __construct() {

  $db_server 				= "localhost";
  $db_user 					= "rstar_core_manager";
  $db_password 	= "r04dst4r";
  $db 									= "Roadstar_Core";

  $db_connection 	= mssql_connect($db_server, $db_user, $db_password);
  $db_select 				= mssql_select_db($db);

  include("_runway/_airbus/project.dbSettings");
  $this->storedProcedures = $storedProcedures;
}

But this is horrible in the sense that the storedProcedures array could get absolutely MASSIVE.

I tried your suggestion of the include_once outside and then pass as an argument, but it wouldn't pass as expected. Unless you have a suggestion as to how to implement your possible solution.

[Shrike]

Including the file for every object creation is an unneccesary overhead anyway and should be avoided.

class ConnectionDB {
  // Might as well pass by reference as the array is big
  function __construct( &$storedProcedures ) {
    ...
    $this->storedProcedures =& $storedProcedures;
   ...
  }
  ...
}
include_once( "_runway/_airbus/project.dbSettings" );
$connectionDb = new ConnectionDb( $storedProcedures );

Does that not work?

[Stathy]

I'd suggest creating a static config class to hold the stored procedure information. Then you can include the class and access the array via accessors and not worry about initializing the array on every object instantiation. It also allows for the configuration class to evolve in the event you want to store it in a database or parse a text file, etc.

Including the stored procedure variable as a global and then using within an object or class is not wise as it increases coupling.

(Not that you have to follow a java example but just the first I googled, feel free to research on your own)
http://javaboutique.internet.com/tutorials/coupcoh/

I wouldn't declare any object attributes as public ... I know it can be a pain in the a$$ to follow these suggestions (more coding, more thought) but it will benefit you over the long run. I know you are just starting out so keep it in mind. If you find it cumbersome to follow some of the fundamental principles it would be better off not using OO.

[Shrike]

I'm not quite sure who you are replying to Stathy, but I will assume me 😉

I don't think theres a great deal of difference between passing a global variable to a class or first wrapping the variable with another class and then calling methods on that. You might only want to deal with classes, and as you say might provide some future proofing.

The original post is strongly coupled due to including the file within the constructor. Using a function parameter to pass a dependency moves the responsibility of locating the resource outside of the class, so creating a loose coupling.

[sakurachan]

Hey guys, thanks for the tips.

Shrike: I've tried your suggestion by calling the __construct(&$storedProcedures) and it works nicely. So it is at this point resolved.

I've decided though to run with the config class suggestion, only because I feel I'd like to work soley with class and since I can access the array purely by reference this should cut down on some of the overheads in the app. I maybe wrong as I am still new to this, but I believe that this app must by designed and implemented in an OOP manner purely because the app goal is of a OO nature.

Stathy: Thanks for the idea of the config class I'll roll with this and see how I go. As I said I am only starting out in this whole OOP business in PHP, but I won't be backing down all that easy, cumbersome or not 😉

Thanks again