在方法调用返回的字符串上使用str_replace

This is the client code; I want to surround the the myReplaceRR inside the Magento string:

BEFORE

$myReplaceRRR=stripslashes($product_description);
$myReplaceRRR=str_replace("bespoke.php", "made-to-measure.php", $myReplaceRRR);
$myReplaceRRR=str_replace("***OFFER PRICE FOR A LIMITED PERIOD ONLY***", "<span style=\"color:#ed2929\">***OFFER PRICE FOR A LIMITED PERIOD ONLY***</span>", $myReplaceRRR);
echo $myReplaceRRR;

AFTER

$myReplaceRRR= $this->getChildHtml('description');
$myReplaceRRR=stripslashes($product_description);
$myReplaceRRR=str_replace("bespoke.php", "made-to-measure.php", $myReplaceRRR);
$myReplaceRRR=str_replace("***OFFER PRICE FOR A LIMITED PERIOD ONLY***", "<span style=\"color:#ed2929\">***OFFER PRICE FOR A LIMITED PERIOD ONLY***</span>", $myReplaceRRR);
echo $myReplaceRRR;

Note, I want this as a string $this->getChildHtml('description');

You should really try to be more descriptive in your question.

Remove the second line?

$myReplaceRRR= $this->getChildHtml('description');
$myReplaceRRR=str_replace("bespoke.php", "made-to-measure.php", $myReplaceRRR);
$myReplaceRRR=str_replace("***OFFER PRICE FOR A LIMITED PERIOD ONLY***", "<span style=\"color:#ed2929\">***OFFER PRICE FOR A LIMITED PERIOD ONLY***</span>", $myReplaceRRR);
echo $myReplaceRRR;