The function json_encode can serialize any PHP variable into JSON format.
$arr = array('a'=>1,'b'=>2,'c'=>3);
echo json_encode($arr);
This PHP code will output:
{"a":1,"b":2,"c":3}
The thing is, json_encode is only defaultly compiled with PHP 5 and above, and if you can’t install new modules into your server, you can’t have the new native function. Luckily somebody has a clean PHP script version of it so you can define the function yourself, save this to a file and include it everytime you’ll need it.
if (!function_exists('json_encode'))
{
function json_encode($a=false)
{
if (is_null($a)) return 'null';
if ($a === false) return 'false';
if ($a === true) return 'true';
if (is_scalar($a))
{
if (is_float($a))
{
// Always use "." for floats.
return floatval(str_replace(",", ".", strval($a)));
}
if (is_string($a))
{
static $jsonReplaces = array(array("\\", "/", "\n", "\t", "\r", "\b", "\f", '"'), array('\\\\', '\\/', '\\n', '\\t', '\\r', '\\b', '\\f', '\"'));
return '"' . str_replace($jsonReplaces[0], $jsonReplaces[1], $a) . '"';
}
else
return $a;
}
$isList = true;
for ($i = 0, reset($a); $i < count($a); $i++, next($a))
{
if (key($a) !== $i)
{
$isList = false;
break;
}
}
$result = array();
if ($isList)
{
foreach ($a as $v) $result[] = json_encode($v);
return '[' . join(',', $result) . ']';
}
else
{
foreach ($a as $k => $v) $result[] = json_encode($k).':'.json_encode($v);
return '{' . join(',', $result) . '}';
}
}
}