WDDX Functions

Introduction

These functions are intended for work with » WDDX.

Requirements

In order to use WDDX, you will need to install the expat library (which comes with Apache 1.3.7 or higher).

Installation

After installing expat compile PHP with --enable-wddx.

The windows version of PHP has built in support for this extension. You do not need to load any additional extension in order to use these functions.

Runtime Configuration

This extension has no configuration directives defined in php.ini.

Resource Types

This extension defines a WDDX packet identifier returned by wddx_packet_start().

Predefined Constants

This extension has no constants defined.

Examples

All the functions that serialize variables use the first element of an array to determine whether the array is to be serialized into an array or structure. If the first element has string key, then it is serialized into a structure, otherwise, into an array.

Example 2612. Serializing a single value with WDDX

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<?php
echo wddx_serialize_value("PHP to WDDX packet example", "PHP packet");
?>

This example will produce:

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<wddxPacket version='1.0'><header comment='PHP packet'/><data>

<string>PHP to WDDX packet example</string></data></wddxPacket>

Example 2613. Using incremental packets with WDDX

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<?php

$pi = 3.1415926;
$packet_id = wddx_packet_start("PHP");
wddx_add_vars($packet_id, "pi");

/* Suppose $cities came from database */
$cities = array("Austin", "Novato", "Seattle");
wddx_add_vars($packet_id, "cities");

$packet = wddx_packet_end($packet_id);

echo $packet;
?>

This example will produce:

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<wddxPacket version='1.0'><header comment='PHP'/><data><struct>

<var name='pi'><number>3.1415926</number></var><var name='cities'>

<array length='3'><string>Austin</string><string>Novato</string>

<string>Seattle</string></array></var></struct></data></wddxPacket>

Note:

If you want to serialize non-ASCII characters you have to convert your data to UTF-8 first (see utf8_encode() and iconv()).

Table of Contents

wddx_add_vars — Add variables to a WDDX packet with the specified ID
wddx_deserialize — Alias of wddx_unserialize()
wddx_packet_end — Ends a WDDX packet with the specified ID
wddx_packet_start — Starts a new WDDX packet with structure inside it
wddx_serialize_value — Serialize a single value into a WDDX packet
wddx_serialize_vars — Serialize variables into a WDDX packet
wddx_unserialize — Unserializes a WDDX packet

Code Examples / Notes » ref.wddx

With ref to the above comment about typing, I have found that -- oddly enough -- PHP's WDDX supports the following WDDX types: null, boolean (true/false), number and string, *but* not date-time. as an example, use the following values in an array that you then serialize: $number = 5, $null = NULL, $bool = true, $string = 'this is a string'. they will all serialize correctly, e.g. the third entry comes out as: <var name='bool'><boolean value='true'/></var> i have tried with the 'official' format for WDDX 'datetime', e.g. '1998-9-15T09:05:32+4:0' (from the DTD @ http://www.openwddx.org/downloads/dtd/wddx_dtd_10.txt) but have only succeeded in getting this encoded as a 'string' type. if anyone else has any more information on this, it would be welcome. i would like to store the variables in 'appropriate' fields in a database, and the fact that only datetime is not supported is slightly irritating -- otherwise it would be a very useful function.

I think it would be helpful for passing data between languages to show a direct translation of the above examples into Perl, using WDDX.pm 1.00 from CPAN. It took me awhile to figure out. To serialize: <PRE> #!/usr/bin/perl use WDDX; $wddx = new WDDX; $packet_id = $wddx->struct({}); $pi = 3.1415926; $packet_id->set("pi" => $wddx->number($pi)); # Suppose @cities came from database @cities = ("Austin", "Novato", "Seattle"); $packet_id->set("cities" => $wddx->array([map $wddx->string($_), @cities])); $packet = $wddx->serialize($packet_id); open(FP, ">cities.wddx"); print FP $packet; close(FP); </PRE> To deserialize: <PRE> #!/usr/bin/perl use WDDX; open(FP, "<cities.wddx"); undef $/; # Slurp the whole file. $packet = <FP>; close(FP); $packet_id = new WDDX; $wddx_obj = $packet_id->deserialize($packet); $value = $wddx_obj->as_hashref(); print "pi is: " . $value->{"pi"} . " \n"; print "cities is: \n"; $key = 0; foreach $val (@{$value->{"cities"}}) { print "$key => $val \n"; $key++; } </PRE>

WDDX Functions

Introduction

Requirements

Installation

Runtime Configuration

Resource Types

Predefined Constants

Examples

Example 2612. Serializing a single value with WDDX

Example 2613. Using incremental packets with WDDX

Code Examples / Notes » ref.wddx

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