Adding database name within the initial parameters

[9three]

Hey,

 

What I'm trying to accomplish is add the database name within the first line to avoid having two lines. This is what I mean:

 

$connection = new mysql('localhost', 'root', '', 'cms');
$query = "SELECT ID, Username, Password, Email FROM admins";
$connection->query($query);

 

It's throwing me an exception saying that I did not select a database.

 

I'm trying to avoid this:

 

$connection = new mysql('localhost', 'root', '');
$connection->select(cms);
$query = "SELECT ID, Username, Password, Email FROM admins";
$connection->query($query);

 

Here is my class file:

 

  public function __construct($host = '', $username = '', $password = '', $dbname = '')
  {
    $this->host = $host;
    $this->username = $username;
    $this->password = $password;
    $this->dbname = $dbname;
    $this->connect();
  }
  
  public function connect()
  {
    $this->link = mysql_connect($this->host, $this->username, $this->password);
    if (!is_resource($this->link))
      Throw New Exception(mysql_error());
    else
      return $this->link;
  }
  
  public function select()
  {
    $this->select = mysql_select_db($this->dbname, $this->link);
    if (!is_resource($this->select))
      Throw New Exception(mysql_error());
    else
      return $this->select;
  }

 

I thought this was the way to do it but I guess I was wrong. Anyone know how to fix the parameters?

[Brian W]

Does it work with that one line added? If so, dude, its one line! Add it and get on with it.

Btw, you should only need to say it once per page, so we are only talking one line per page. No big deal.

[gevans]

Why do you want to avoid the second line? You need it..

 

Unless you add another line to your class method selecting the database after a successful conection.

[Brian W]

Try:

  public function __construct($host = '', $username = '', $password = '', $dbname = '')
  {
    $this->host = $host;
    $this->username = $username;
    $this->password = $password;
    $this->dbname = $dbname;
    $this->connect();
    $this->select();//If I understand correctly (I don't use classes much yet), this will do it.
  }

Sorry for being dramatic before. Now I see where you are going with it, I think.

[9three]

Try:

  public function __construct($host = '', $username = '', $password = '', $dbname = '')
  {
    $this->host = $host;
    $this->username = $username;
    $this->password = $password;
    $this->dbname = $dbname;
    $this->connect();
    $this->select();//If I understand correctly (I don't use classes much yet), this will do it.
  }

Sorry for being dramatic before. Now I see where you are going with it, I think.

 

Doesn't work.

[Brian W]

error message? doesn't select db but returns no error? whats going on?

[9three]

Throws another Exception now within my constructor on the first line.

[Brian W]

There is a hint of information online I am still researching but it suggests that you can not return objects in your constructor. If this is true, you will need to call both connect() and select() outside of new mysql() and

your __construct() function

 

Does connect() work from the __construct?

[9three]

When you input a 'function' into the constructor it's called a method. And yes, $this->connect() works fine in the constructor.

[gevans]

try this;

 

  public function __construct($host = '', $username = '', $password = '', $dbname = '')
  {
    $this->host = $host;
    $this->username = $username;
    $this->password = $password;
    $this->dbname = $dbname;
    $this->connect();
  }
  
  public function connect()
  {
    $this->link = mysql_connect($this->host, $this->username, $this->password);
    if (!is_resource($this->link))
      Throw New Exception(mysql_error());
    else {
     $this->select();
      return $this->link;
   }
  }
  
  public function select()
  {
    $this->select = mysql_select_db($this->dbname, $this->link);
    if (!is_resource($this->select))
      Throw New Exception(mysql_error());
    else
      return $this->select;
  }

 

If it doesn't work post the error message

[9three]

That puts me back to square one.

 

Fatal error: Uncaught exception 'Exception' with message 'No database selected' in C:\Users\9three\Desktop\Server\htdocs\gb\library\mysql.class.php:40 Stack trace: #0 C:\Users\9three\Desktop\Server\htdocs\gb\index.php(10): mysql->query('SELECT ID, User...') #1 {main} thrown in C:\Users\9three\Desktop\Server\htdocs\gb\library\mysql.class.php on line 40

[premiso]

Why are you putting the select in a different function if you are not even providing the option to add a different database as a parameter?

 

<?php
class mysql {
  private $host, $username, $password, $dbname;

  public function __construct($host = '', $username = '', $password = '', $dbname = '')
  {
    $this->host = $host;
    $this->username = $username;
    $this->password = $password;
    $this->dbname = $dbname;
    $this->connect();
    $this->select();
  }
  
  public function connect()
  {
    $this->link = mysql_connect($this->host, $this->username, $this->password);

    if (!is_resource($this->link))
      Throw New Exception(mysql_error());

    return $this->link;
   
  }
  
  public function select($dbname='') {
    if (isset($dbname) && !empty($dbname)) {
         $this->dbname = $dbname;
    }

    $this->select = mysql_select_db($this->dbname, $this->link);
    if (!is_resource($this->select))
      Throw New Exception(mysql_error());
    else
      return $this->select;
  }
?>

 

Now this code:

 

$connection = new mysql('localhost', 'root', '');
$connection->select('cms'); // note quotes
$query = "SELECT ID, Username, Password, Email FROM admins";
$connection->query($query);

 

Should work. It should also work with the db being passed in as a parameter to the constructor.

[9three]

I am allowing the change of database in the parameters

 

//host, username, password, database name
public function __construct($host = '', $username = '', $password = '', $dbname = '')

 

//host = localhost, username = root, password = blank, database = cms
$connection = new mysql('localhost', 'root', '', 'cms');

[premiso]

I am allowing the change of database in the parameters

 

//host, username, password, database name
public function __construct($host = '', $username = '', $password = '', $dbname = '')

 

//host = localhost, username = root, password = blank, database = cms
$connection = new mysql('localhost', 'root', '', 'cms');

 

Right, but you were using the $connection->select and trying to pass a parameter that way, which it does not accept a parameter.

[9three]

I don't want to use the object of $connection->select(); I want to avoid that.

 

I'm trying to execute connecting and selecting the database when I first initiate the object.

[premiso]

I don't want to use the object of $connection->select(); I want to avoid that.

 

I'm trying to execute connecting and selecting the database when I first initiate the object.

 

In the revised code I posted that is done. I added functionality to the select(). But if you call connect() it does it automatically. However if you want to change the DB at any time you just call $connection->select('newdbhere');

 

Look over my revision to see the changes.

 

$connection = new mysql('localhost', 'root', '', 'cms');
$query = "SELECT ID, Username, Password, Email FROM admins";
$connection->query($query);

 

Should work, given the code I modified above.

[9three]

hm.. I see what you did there. I remember seeing some code some time ago and it was handled differently. Thanks for the input.