Formatting of Numbers with PDO - php

Question

I have recently moved a large php application from using mssql_ functions to the PDO function using the mssql driver.
I wrote a simple library that allows drop in replacement. It all seems to work pretty well considering.
However one thing that is a bit annoying is default format of numbers and particularly numbers defined as money in the database.
Most of my smarty template pages previous simply output the number as it came from the database so someones balance might be show as
125.00
however since changing to PDO this is returned as
125.0000
This is a little annoying and off putting, but obviously not the end of the world.
My Question. Is there a workaround / trick / formatting Constant or method that I can use to get PDO to format values differently, or do I need to go an manually set the format for every number in every template throughout my app?

Answer 1

So basically, what I'd do is create models that represent a result-set for each table, and use PDO::FETCH_CLASS to load the data into instances of the corresponding class. For example:
class UserTable //extends AbstractTable <-- see below
{
protected $id = null;
protected $name = null;
protected $email = null;
protected $money = null;
}
Then add getters and setters that format/validate the data accordingly eg:
public function getMoney()
{
return sprintf('%.2f', $this->money);//check if not null first, obviously
}
Next, have an abstract class for these models, and implement the ArrayAccess interface in there. For example, using a simple mapping array:
protected $getterMap = [
'email' => 'getEmail',
'id' => 'getId',
'money' => 'getMoney',
];
Define a tailor-made map in each child, then have the abstract class use it like so:
//in abstract class AbstracTable implements ArrayAccess
public function offsetGet($offset)
{
if (!isset($this->getterMap[$offset])) {
throw new RuntimeException(
sprintf('%s not a member of %s', $offset, get_class($this));
);
}
$getter = $this->getterMap[$offset];
return $this->{$getter}();//use the getter, it formats the data!
}
Do something similar for all 4 methods in the interface, and now you can use this:
$row = $stmt->fetch(PDO::FETCH_CLASS, 'User');
$row['money'];//will call getMoney, and return the formatted number
A more complete example:
abstract class AbstractTable implements ArrayAccess
{
protected $id = null;//very likely to be defined in all tables
protected $getterMap = [
'id' => 'getId',
];
protected $setterMap = [
'id' => 'setId',
];
//force child classes to define a constructor, which sets up the getter/setter maps
abstract public function __construct();
public offsetExists($offset)
{
return isset($this->getterMap[$offset]);
//optionally, check if value if not null: isset($arr['keyWithNullVal']) returns null, too:
return isset($this->getterMap[$offset]) && $this->{$offset} !== null;
}
public offsetGet ( mixed $offset )
{
if (!isset($this->getterMap[$offset])) {
throw new RuntimeException('member does not exist');
}
$getter = $this->getterMap[$offset];
return $this->{$getter}();
}
public offsetSet($offset, $value )
{
if (!isset($this->setterMap[$offset])) {
throw new RuntimeException('Trying to set non-existing member');
}
$setter = $this->setterMap[$offset];
$this->{$setter}($value);
}
public offsetUnset ($offset)
{
//same as setter, but call:
//or just leave blank
$this->{$setter}(null);
}
}
class UserTable extends AbstractTable
{
//protected $id = null; in parent already
protected $name = null;
protected $email = null;
protected $money = null;
public function __construct()
{
$fields = [
'name' => 'etName',
'email' => 'etEmail',
'money' => 'etMoney',
];
foreach ($fields as $name => $method) {
$this->getterMap[$name] = 'g' . $method;
$this->setterMap[$name] = 's' . $method;
}
}
}
Obviously, you'll have to write the getters and setters for all the fields. Not to worry, though: most IDE's will helpfully generate the getters and setters for predefined properties at the click of a button