CII. WDDX Functions

To make these examples work, you'll probably want to format the output with
a call to htmlentities:

<pre>
$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);
print htmlentities($packet);
</pre>

Since there aren't any examples of reversing the process, here's one. If
you had the packet produced by the above example (without the
htmlentities() call), you could retrieve the values like this:

<pre>
$value = wddx_deserialize($packet);
print "pi is:
" . $value["pi"] .
"
\n";
print "cities is:
\n";
while (list($key, $val) = each($value["cities"])) {
	print "$key => $val
\n";
}
</pre>

which outputs:

<pre>
pi is:
3.1415926

cities is:
0 => Austin
1 => Novato
2 => Seattle
</pre>

The PHP WDDX module encodes all scalars as strings in the XML packet, due
to PHP's loose typing.  The current Perl WDDX module takes a different
approach, requiring the caller to mark each variable with a type.  This is
helpful if the reader of the packet is a more strongly typed language that
distinguishes between string, int, float, and bool; but it's more
cumbersome to use than the PHP approach.  The Perl module is hard to find
right now; its home page is:


<a href=">>

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>

Here's a rewrite of the deserializing Perl code that uses variable names
consistently with the serializing example.  Sorry for any confusion....
<PRE>
#!/usr/bin/perl

use WDDX;

open(FP, "<cities.wddx");
undef $/;                       # Slurp the whole file.
$packet = <FP>;
close(FP);

$wddx = new WDDX;
$packet_id = $wddx->deserialize($packet);
$value = $packet_id->as_hashref();

print "pi is:
" . $value->{"pi"} .
"
\n";
print "cities is:
\n";
$key = 0;
foreach $val (@{$value->{"cities"}}) {
    print "$key => $val
\n";
    $key++;
}
</PRE>

If you take a wddx recordset (I.E. in Cold Fusion) will Deserializing the
packet create a Result varible?

Tutorial here :

XML and PHP. Part 1: Using the WDDX functions