Zend Framework by examples (ZfEx): Connect to a database

In this example, we implement a connection to a database.

Components used in this example

MyDbConnection MyHtml Entry point HTML | Try it | View source code

Implementation of the connection


class MyDbConnection
{

The connection process

We get the connection method from the GET request.
We connect with the database adapter, the factory method, or the configuration.
We get the configuration details.


    public function process()
    {
        // We get the connection method from the GET request.
        list($method) = $this->_getParameters();

        // We connect with the database adapter, the factory method, or the configuration.
        switch ($method) {
            case 'Zend_Db Adapter':
                $db = new Zend_Db_Adapter_Pdo_Sqlite(array('dbname' => ':memory:'));
                break;

            case 'Zend_Db Factory':
                $db = Zend_Db::factory('Pdo_Sqlite', array('dbname' => ':memory:'));
                break;

            case 'Zend_Config':
                $config = new Zend_Config(array(
                    'database' => array(
                        'adapter' => 'Pdo_Sqlite',
                        'params'  => array('dbname' => ':memory:')
                    )
                ));
                $db = Zend_Db::factory($config->database);
                break;
        }

        // We get the configuration details.
        $message = isset($db)? $db->getConfig() : array();

        return array($method, $message);
    }

Extraction of the parameters from the GET request


    private function _getParameters()
    {
        $method = isset($_GET['method'])? $_GET['method'] : '';

        return array($method);
    }

Displaying items


class MyHtml
{

Displaying the title of the page based on the file name.


    public static function printTitle()
    {
        $basename = basename(__FILE__, '.php');
        $title = ucwords(str_replace('-' , ' ', $basename));
        $zfVersion = Zend_Version::VERSION;
        $phpVersion = phpversion();
        echo "ZfEx $title (ZF/$zfVersion PHP/$phpVersion)";
    }

Displaying the selected option


    public static function printSelected($value, $target)
    {
        $value == $target and print 'selected="selected"';
    }

Colorization of data

We export the data as valid PHP code.
We add the PHP tag, we colorize the code, we remove the PHP tag.
We display the data.


    public static function colorize($mixed)
    {
        // We export the data as valid PHP code.
        $mixed = var_export($mixed, true);
        // We add the PHP tag, we colorize the code, we remove the PHP tag.
        $mixed = '<?' . "php $mixed";
        $mixed = highlight_string($mixed, true);
        $mixed = str_replace('&lt;?php&nbsp;', '', $mixed);
        // We display the data.
        echo "<pre>$mixed</pre>";
    }

Processing the connection

We get the connection method and the database configuration, to display in the form.


$dbConnection = new MyDbConnection;
// We get the connection method and the database configuration, to display in the form.
list($method, $message) = $dbConnection->process();


<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title><?php MyHtml::printTitle();?></title>
    <style type="text/css">
      body{
          font-family: arial, sans-serif;
          font-size: 0.9em;
      }
      pre {
          margin-top: 0;
      }
    </style>
  </head>

  <body>

    <p>EXAMPLE <?php MyHtml::printTitle();?></p>
    <hr />

    <form>
      Select a connection method:
      <select name="method" value="<?php echo $method;?>">
        <option <?php MyHtml::printSelected($method, 'Zend_Db Adapter');?>>Zend_Db Adapter</option>
        <option <?php MyHtml::printSelected($method, 'Zend_Db Factory');?>>Zend_Db Factory</option>
        <option <?php MyHtml::printSelected($method, 'Zend_Config');?>>Zend_Config</option>
      </select>


      <input type="submit" value="Submit" />
    </form>

    <hr />
    CONNECTION RESULT
    <?php MyHtml::colorize($message);?>

  </body>
</html>