Replace with Dynamic variable in preg_replace

[MarPlo]

Hi
I'm trying the following code:

$t = '12<-- AB_C -->';
$AB_C = 'abc';
echo preg_replace('/\<-- ([A-Z_]+) --\>/', "$$1", $t);

I want to get "12abc" , but it outputs: 12$AB_C , so, it not recognize the replacement as dynamic variable.
Is it any way to use the matched word in preg_replace() as a variable, or dynamic variable?

MarPlo Reviewed by MarPlo on 20th Feb 2012. Replace with Dynamic variable in preg_replace Hi I'm trying the following code: $t = '12<-- AB_C -->'; $AB_C = 'abc'; echo preg_replace('/\<-- (+) --\>/', "$$1", $t); I want to get "12abc" , but it outputs: 12$AB_C , so, it not recognize the replacement as dynamic variable. Is it any way to use the matched word in preg_replace() as a variable, or dynamic variable? Rating: 5

[Lock Down]

I am not really sure what you are trying to do here.

If you are trying to get the contents of the variable $AB_C to replace the string "<-- AB_C -->" in the example or what?

But if that is the case just use this:

<?php
$t = '12<-- AB_C -->';
$AB_C = 'abc';
echo preg_replace('/\<-- ([A-Z_]+) --\>/', &$AB_C, $t);
?>

[MarPlo]

Hi,
I solved the problem using the "/e" flag, which makes the preg_replace() to evaluate the expresion before replacement.

preg_replace('/\<-- ([A-Z_]+) --\>/e', "$$1", $t);