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@NogDogNov 21.2021 — #
That being said, I don't see why you need both the
Then if you do
Assuming that
This avoids the use of
Frankly, if the only reason for that
Then they have not been defined in that context -- but without seeing the class definition, I cannot be sure exactly why. But this is all trying to resolve a problem that shouldn't need solving: creating a database connection in more than one place. I _strongly_ recommend creating your PDO object once, and then passing it in to any class or function that needs to use it. You almost always do not want to create multiple database connections within one PHP script.@NogDogDec 01.2021 — #
Not sure I follow.
Unless you're dealing with multiple databases, you only ever need one database connection. Since a PDO object is created with a database connection, you only need one PDO object in that case. So, what is the purpose of having this
Now you can either usehttps://www.webdeveloper.com/d/397887-required-file-config-undefined-property-dsn/4 I showed you how to pass your @ginerjm#1640078 Yep, at least as I see it, the
Required file (Config) Undefined Property dsn
Looking at PDO tutorials on YouTube and PHP forums trying to figure this out.
This is my Config.php
“`
$db = new Db;
class Db
{
private $host;
private $dbName;
public $user;
public $pass;
public function Connect()
{
$this->host = ‘localhost’;
$this->dbName = ‘core’;
$this->user = ‘root’;
$this->pass = ”;
try
{
$dsn = “mysql:host=”.$this->host.”;dbName=”.$this->dbName;
$pdo = new PDO($dsn, $this->user, $this->pass);
$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
}
catch (PDOException $e)
{
echo ‘Error: ‘.$e->getMessage();
}
}
}
This is Data.php
“`
require ‘Config.php’;
$data = new Data;
class Data
{
public function __construct()
{
global $db;
try
{
$pdo = new PDO($db->dsn,$db->user,$db->pass);
}
catch (PDOException $e)
{
echo ‘Error’ . $e->getMessage();
}
}
I am getting Undefined Property Db::$dsn in Data.php $dsn is a variable in Config.php, so why is it saying Undefined Property? Appreciate any help, guidance with this.
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0
@NogDogNov 21.2021 — #$dsn__construct()public$this->dsnThat being said, I don't see why you need both the
DBDataglobal<i>
</i>class Db extends PDO // Assuming all we really need is a PDO object
{
private $host = 'localhost';
private $dbName = 'core';
private $user = 'root';
private $pass = 'pass';
public function Connect()
{
$dsn = "mysql:host=".$this->host.";dbName=".$this->dbName;
try {
// now we can call the parent PDO constructor:
parent::__construct($dsn, $this->user, $this->pass);
$this->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
} catch (PDOException $e) {
echo 'Error: '.$e->getMessage();
}
}
}
Then if you do
$data = new Db();$data0
@NogDogNov 22.2021 — #>@rpjd1#1639708 Then I don't need this...in Data.php?
Assuming that
Data<i>
</i>require 'Config.php'; // creates the $db object
$data = new Data($db); // pass it in to your Data object
class Data {
private $db;
public function __construct(PDO $db) {
$this->db = $db;
}
public some_data_thing() {
// Can now use $this->db to do any PDO stuff
}
}
This avoids the use of
globalData0
@NogDogNov 22.2021 — #The function name for the DB__construct()PDO0
@NogDogNov 22.2021 — #PS: Using this forum's ...</>0
@NogDogNov 23.2021 — #No, I'm calling the parent constructor via parent::__construct()Frankly, if the only reason for that
Db$_ENV0
@NogDogNov 30.2021 — #>@rpjd1#1640039 This line is giving me Undefined Property for dsn, Undefined variable for user and pass
Then they have not been defined in that context -- but without seeing the class definition, I cannot be sure exactly why. But this is all trying to resolve a problem that shouldn't need solving: creating a database connection in more than one place. I _strongly_ recommend creating your PDO object once, and then passing it in to any class or function that needs to use it. You almost always do not want to create multiple database connections within one PHP script.
0
@NogDogDec 01.2021 — #>@rpjd1#1640074 It's my understanding, using a connection class as above requires a constructor in the class that queries the database which is executed automatically when an object of the class is created.
Not sure I follow.
Unless you're dealing with multiple databases, you only ever need one database connection. Since a PDO object is created with a database connection, you only need one PDO object in that case. So, what is the purpose of having this
Db[code=php]
class Db extends PDO {
private $host = "localhost";
private $user = "root";
private $pass = "";
private $dbName = "dbName";
private $charset = "utf8mb4";
public function __construct() {
$dsn = "mysql:host={$this->host};dbName={$this->dbName};charset={$this->charset}";
parent::__construct($dsn, $this->user, $this->pass, array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION));
}
}
// use it:
try {
$pdo = new Db();
} catch (PDOException $e) {
die('Error: '.$e->getMessage());
}
[/code]Now you can either use
$pdo0
@NogDogDec 01.2021 — #If you go back to Db$this->db0
@NogDogDec 01.2021 — #Db