PHP serialization format
From HandWiki - Reading time: 3 min
The PHP serialization format is the serialization format used by the PHP programming language. The format can serialize PHP's primitive and compound types, and also properly serializes references.[1] The format was first introduced in PHP 4.[2]
In addition to PHP, the format is also used by some third-party applications that are often integrated with PHP applications, for example by Lucene/Solr.[3]
Syntax
The syntax generally follows the pattern of one-letter code of the variable type, followed by a colon and the length of the data, followed by the variable value, and ending with a semicolon. For the associative array, the format is <serialised key> ; <serialised value>, repeated for each association/pair in the array.
| Type | Serialization examples |
|---|---|
| Null | N;
|
| Boolean | b:1;b:0;
|
| Integer | i:685230;i:-685230;
|
| Floating point | d:685230.15;d:INF;d:-INF;d:NAN;
|
| String | s:5:"apple";s:6:"A to Z";
|
| Associative array | a:4:{i:0;b:1;i:1;N;i:2;d:-421000000;i:3;s:6:"A to Z";}a:2:{i:42;b:1;s:6:"A to Z";a:3:{i:0;i:1;i:1;i:2;i:2;i:3;}}
|
| Object | O:8:"stdClass":2:{s:4:"John";d:3.14;s:4:"Jane";d:2.718;}
|
| Reference | a:2:{i:0;s:3:"foo";i:1;R:2;}
|
References
- ↑ "Serialization". http://www.phpinternalsbook.com/php5/classes_objects/serialization.html.
- ↑ "PHP: serialize - Manual". https://www.php.net/manual/en/function.serialize.php.
- ↑ "Response Writers | Apache Solr Reference Guide 8.5". https://lucene.apache.org/solr/guide/8_5/response-writers.html#php-writer.
External links
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|---|---|---|
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Licensed under CC BY-SA 3.0 | Source: https://handwiki.org/wiki/PHP_serialization_format20 views | Status: cached on January 31 2026 13:51:40↧ Download this article as ZWI file
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