A little doubt about PHP's handling of XML

A small question about PHP handling XML
Recently in the Pondering interface
Got a little problem.
If there is a variable that reads as follows

$test = "
 
 
  
  11111111
  
  
  
  

  
  11111111
  
  
  
  

  
  
   
   1111
  
  
  
  

  
  text
  
  
  
  

  
  test
  
  
  
  

  
  
   
   111111
  
  
  
  

 
 ";

$POSTOBJ = simplexml_load_string ($test, ' simplexmlelement ', libxml_nocdata);
After reading XML to a variable with simplexml_load_string
$POSTOBJ->addchild ("id", "123");
I added an element.
Now how to restore the contents of the variable into XML format?

------Solution--------------------
You can write it back.
$test = $POSTOBJ->savexml ();

Note, however, that you have the Libxml_nocdata parameter when you open it, so there are no CDATA nodes to write back.

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