interface pq\Converter

Interface for type conversions.

Example:

<?php

/**
 * Naive geometric point
 */
class Point {
    public $x;
    public $y;
    function __construct($x, $y) {
        $this->x = $x;
        $this->y = $y;
    }
}

/**
 * A simple Box
 */
class Box {
    public $p1;
    public $p2;
    function __construct(Point $p1, Point $p2) {
        $this->p1 = $p1;
        $this->p2 = $p2;
    }
}

/**
 * Our converter handles only objects of type box
 */
class BoxConverter implements pq\Converter {
    private $oid;
    function __construct(pq\Types $types) {
        $this->oid = $types["box"]->oid;
    }

    /**
     * @return array
     * @see pq\Converter::convertTypes()
     */
    function convertTypes() {
        return [$this->oid];
    }

    /**
     * @return string
     * @param $box Box
     * @see pq\Converter::convertToString()
     */
    function convertToString($box, $type) {
        return sprintf("(%F,%F),(%F,%F)", 
            $box->p1->x, $box->p1->y,
            $box->p2->x, $box->p2->y
        );
    }

    /**
     * @return Box
     * @param string $data
     * @see pq\Converter::convertFromString()
     */
    function convertFromString($data, $type) {
        list($p1x, $p1y, $p2x, $p2y) = sscanf($data, "(%f,%f),(%f,%f)");
        return new Box(new Point($p1x, $p1y), new Point($p2x, $p2y));
    }
}

$conn  = new pq\Connection;
$types = new pq\Types($conn);
$conv  = new BoxConverter($types);
$inbox = new Box(new Point(1.1, 2.2), new Point(3.3, 4.4));

$conn->setConverter($conv);
$result = $conn->execParams("SELECT \$1", [$inbox], [$types["box"]->oid]);
$result->fetchCol($outbox);

var_dump($outbox);

?> 

Yields:

object(Box)#163 (2) {
  ["p1"]=>
  object(Point)#164 (2) {
    ["x"]=>
    float(3.3)
    ["y"]=>
    float(4.4)
  }
  ["p2"]=>
  object(Point)#165 (2) {
    ["x"]=>
    float(1.1)
    ["y"]=>
    float(2.2)
  }
}

Functions: