Making Friends And Influencing People - PHP

Now, while all this is fine and dandy, how about using all this new-found knowledge for something practical?

This next example does just that, demonstrating how the XMLTree class can be used to convert data stored in a MySQL database into an XML document, and write it to a file for later use. Here's the MySQL table I'll be using,

+----+------------------+-----------------------------------+-----------
+----+------------------+-----------------------------------+----
--+----------------+
| 
id | name             | address                           | tel
|fax       
|
+----+------------------+-----------------------------------+-----------
+----+------------------+-----------------------------------+----
--+----------------+
| 
1 | Sam Spade        | 134, Dark Road, New York, NY      |
1-800-TOUGH-GUY |1-234-587-3636 
|
|  2 | The White Rabbit | Down The Rabbit Hole, Wonderland  | 56-78-5467
|56-78-2537 
|
|  3 | Jack Liliput     | The Little House, Lilliput Island 
| None
|None 
|
+----+------------------+-----------------------------------+-----------
+----+------------------+-----------------------------------+----
--+----------------+

and here's what I want my target XML document to look like:

<?xml version="1.0"?>
<addressbook>
<item id="1">
<name>Sam 
Spade</name>
<address>134, Dark Road, New York, NY</address>
<tel>1-800-TOUGH-GUY</tel>
<fax>1-234-587-3636</fax>
</item>
<item 
id="2">
<name>The White Rabbit</name>
<address>Down The Rabbit 
Hole, Wonderland</address>
<tel>56-78-5467</tel>
<fax>56-78-2537</fax>
</item>
<item id="3">
<name>Jack 
Liliput</name>
<address>The 
Little House, Lilliput Island</address>
<tel>None</tel>
<fax>None</fax>
</item>
</addressbook>

With XMLTree, accomplishing this is a matter of a few lines of code. Here they are:

<?php
// include class
include("Tree.php");
// set output filename
$filename 
= 'addressbook.xml';
// instantiate object
$tree  = new XML_Tree();
// add 
the 
root element
$root =& $tree->addRoot("addressbook");
// open connection 
to 
database
$connection = mysql_connect("localhost", "joe", "secret") or die 
("Unable 
to
connect!");
// select database
mysql_select_db("db567") or die 
("Unable 
to 
select database!");
// execute query
$query = "SELECT * FROM addressbook";
$result 
= mysql_query($query) or die ("Error in query: $query. " .
mysql_error());
// 
iterate through rows and print column data
while ($row = mysql_fetch_array($result))
{
// 
add child elements
$item =& $root->addChild("item", NULL, array("id" => 
$row['id']));
$name 
=& $item->addChild("name", $row['name']);
$address 
=& $item->addChild("address", 
$row['address']);
$tel =& $item->addChild("tel", 
$row['tel']);
$fax =& 
$item->addChild("fax", $row['fax']);
}
// close 
database connection
mysql_close($connection);
// 
open file
if (!$handle = fopen($filename, 
'w')) 
{ 
print "Cannot open file ($filename)";
exit;
}
// 
write XML to file
if 
(!fwrite($handle, $tree->get())) 
{
print "Cannot write 
to file ($filename)";
exit;
}
// 
close file    
fclose($handle);
?>

Pretty simple, once you know how it works. First, I've opened up a connection to the database and retrieved all the records from the table. Then I've instantiated a new document tree and iterated over the result set, adding a new set of nodes to the tree at each iteration. Finally, once all the rows have been processed, the dynamically generated tree is written to a file for later use.

>>> More PHP Articles          >>> More By icarus, (c) Melonfire

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