如果包含使用正则表达式的字符串，则替换父XML标记

I have the following XML :

我有以下XML:

<customer>
   <name>Customer name</name>
   <address>
      <postalcode>94510</postalcode>
      <town>Green Bay</town>
   </address>
   <phone>0645878787</phone>
</customer>
<custom