How to improve the following code in PHP

Question

Hello

Here is a simple form I am using to send XML data in admin_xml.php

<form name="review" action="admin_xml.php" method="post">
 <textarea name="xml" cols="40" rows="10"></textarea>
 <input class="submit" type="submit" value="Submit Request">
</form>

---

Here is the XML which I enter in order to retrieve the data from MySQL Database

<?xml version="1.0" encoding="UTF-8"?>
<GetOrdersIds>
    <Credentials>
        <Username>my_username</Username>
        <Password>my_password</Password>
    </Credentials>
    <Criterions>
        <OrderNumber></OrderNumber>
        <StartDate>2009-01-01</StartDate>
        <EndDate>2009-07-01</EndDate>
    </Criterions>
</GetOrdersIds>

---

Here is the php code which extracts the tags from the xml:

<?php    

$text_all = "<?xml version=\"1.0\"?>\r\n<GetOrdersIds version=\"1.0\">\r\n<Credentials>\r\n<Username>my_username</Username>\r\n<Password>my_password</Password>\r\n</Credentials>\r\n<Criterions>\r\n<OrderNumber></OrderNumber>\r\n<StartDate>2009-01-01</StartDate>\r\n<EndDate>2009-07-01</EndDate>\r\n</Criterions>\r\n</GetOrdersIds>";

$field = "Criterions";

$result = substr($text_all, strpos($text_all, "<".$field.">")+strlen("<".$field.">"), strpos($text_all, "</".$field.">")-strlen("<".$field.">")-strpos($text_all, "<".$field.">"));


?>

The result from the above php code is:

<OrderNumber></OrderNumber>
<StartDate>2009-01-01</StartDate>
<EndDate>2009-07-01</EndDate>

When the script is run, the php code goes through my mysql data, and extracts all orders between the Start Date and the End Date given above.

---

Is there a better way of improving the following php code, so that it performs the same function:

$result = substr($text_all, strpos($text_all, "<".$field.">")+strlen("<".$field.">"), strpos($text_all, "</".$field.">")-strlen("<".$field.">")-strpos($text_all, "<".$field.">"));

This is the code which searches through the xml data and retrieves all the tags.

UPDATE :

Can anyone list the $result code in SimpleXML?

Answer 1

Have a look at the simplexml module.

Answer 2

Use an XML parser like SimpleXML to extract that data:

$doc = simplexml_load_string($_POST['xml']);
$OrderNumber = $doc->Criterions->OrderNumber;
$StartDate = $doc->Criterions->StartDate;
$EndDate = $doc->Criterions->EndDate;

Answer 3

Some temp vars will help and also make it easier to read.

$result = substr($text_all, strpos($text_all, "<".$field.">")+strlen("<".$field.">"), strpos($text_all, "</".$field.">")-strlen("<".$field.">")-strpos($text_all, "<".$field.">"));

Can be rewritten to.

$tagLen = strlen('<'.$field.'>');
$openTag = strpos($text_all, '<'.$field.'>');
$closeTag = strpos($text_all, '</'.$field.'>', $openTag);

$result = substr($text_all, $openTag + $tagLen, $closeTag - $tagLen - $openTag);

or use SimpleXML

$doc = simplexml_load_string($text_all);
echo $doc->Criterions->asXML();

If you want the individual values use this.

$doc = simplexml_load_string($text_all);

echo $doc->Criterions->OrderNumber;
echo $doc->Criterions->StartDate;
echo $doc->Criterions->EndDate;

if you want the element in XML then use asXML():

$doc = simplexml_load_string($text_all);

echo $doc->Criterions->OrderNumber->asXML();
echo $doc->Criterions->StartDate->asXML();
echo $doc->Criterions->EndDate->asXML();

Answer 4

With SimpleXML:

<?php
$xmlSTR = '<?xml version="1.0" encoding="UTF-8"?>
<GetOrdersIds>
    <Credentials>
        <Username>my_username</Username>
        <Password>my_password</Password>
    </Credentials>
    <Criterions>
        <OrderNumber></OrderNumber>
        <StartDate>2009-01-01</StartDate>
        <EndDate>2009-07-01</EndDate>
    </Criterions>
</GetOrdersIds>';

$xml = new SimpleXMLElement($xmlSTR);

echo $xml->Credentials->Username;

//To see the entire structure print_r($xml); as php can access objects as arrays

Answer 5

Assuming your XML string is stored in the variable called $text_all (as you show in your example), this will get you what you want man... :-)

$mysql_stuff = '';
$xml = new SimpleXMLElement($text_all);

foreach($xml->Criterions->children() as $criterion) {
    $mysql_stuff .= $criterion->asXML()."\n";
}
echo $mysql_stuff;

$mysql_stuff will now contain:

<OrderNumber/>
<StartDate>2009-01-01</StartDate>
<EndDate>2009-07-01</EndDate>

I tested this and it works. I hope this answers your question!