PHP Serialization Serialization of different types
Example
Generates a storable representation of a value.
This is useful for storing or passing PHP values around without losing their type and structure.
To make the serialized string into a PHP value again, use unserialize().
Serializing a string
$string = "Hello world";
echo serialize($string);
// Output:
// s:11:"Hello world";
Serializing a double
$double = 1.5;
echo serialize($double);
// Output:
// d:1.5;
Serializing a float
Float get serialized as doubles.
Serializing an integer
$integer = 65;
echo serialize($integer);
// Output:
// i:65;
Serializing a boolean
$boolean = true;
echo serialize($boolean);
// Output:
// b:1;
$boolean = false;
echo serialize($boolean);
// Output:
// b:0;
Serializing null
$null = null;
echo serialize($null);
// Output:
// N;
Serializing an array
$array = array(
25,
'String',
'Array'=> ['Multi Dimension','Array'],
'boolean'=> true,
'Object'=>$obj, // $obj from above Example
null,
3.445
);
// This will throw Fatal Error
// $array['function'] = function() { return "function"; };
echo serialize($array);
// Output:
// a:7:{i:0;i:25;i:1;s:6:"String";s:5:"Array";a:2:{i:0;s:15:"Multi Dimension";i:1;s:5:"Array";}s:7:"boolean";b:1;s:6:"Object";O:3:"abc":1:{s:1:"i";i:1;}i:2;N;i:3;d:3.4449999999999998;}
Serializing an object
You can also serialize Objects.
When serializing objects, PHP will attempt to call the member function __sleep() prior to serialization. This is to allow the object to do any last minute clean-up, etc. prior to being serialized. Likewise, when the object is restored using unserialize() the __wakeup() member function is called.
class abc {
var $i = 1;
function foo() {
return 'hello world';
}
}
$object = new abc();
echo serialize($object);
// Output:
// O:3:"abc":1:{s:1:"i";i:1;}
Note that Closures cannot be serialized:
$function = function () { echo 'Hello World!'; };
$function(); // prints "hello!"
$serializedResult = serialize($function); // Fatal error: Uncaught exception 'Exception' with message 'Serialization of 'Closure' is not allowed'
