Insert string between quotation marks using RegEx - php

Question

I am allowing the user to create XML elements with blank attribute values such as this:
<crimes id="" total="" />
at the same time I am also retrieving an associative array from a database to be used to fill up the attributes that the XML specifies. The array will look like this:
array(
theft => 123,
burglary => 456
)
After retrieving the array, I want to use that array to populate the attribute values of the XML which have been passed in. So as an example, the first array element combined with the example XML would look like this:
<crimes id="theft" total="123" />
Is there a way to use regular expression in PHP to insert the array values between the quotation marks of the XML attributes?

Answer 1

The only time this will work, is if the XML tags you receive are consistent. They need to be the same every time, otherwise there is no pattern, and regex is used for matching patterns.
If your tags will always have id and total, then I can write a regex for it. But if they sometimes have one or the other, it gets too complicated and you need a parser.

Answer 2

Although (as you've been already told) you should better use SimpleXML or DOM for this, here is a custom RegEx solution you asked for:
$list = array(
"theft" => 123,
"burglary" => 456
);
$template = '<crimes id="" total="" />';
foreach($list as $key => $value)
{
$s = preg_replace('/(id=")(")/', '${1}'.$key.'${2}', $template);
$s = preg_replace('/(total=")(")/', '${1}'.$value.'${2}', $s);
echo htmlentities($s)."<br>";
}
Here is its output:
<crimes id="theft" total="123" />
<crimes id="burglary" total="456" />
If "id" or "total" is missing - it just omits it.