stdClass php issue

How can you check if an object of type stdClass is empty in a view?
(I try this because I want to disable a button, like Read More... when there is no text to read more..)
I've tried:

  <?php 
   if (is_null($fields['body']) {
echo "empty";	 
}else{
 echo "not empty";
	   }
   ?>

and

<?php

$mystring= (string)$fields['body'];
   if ((strlen($fields['body'])>0) {
echo "not empty";	 
}else{
 echo "empty";
	   }
   ?>
   

In the first case, I always get not empty, even though there is no text in the object..
The error showing when I try converting to string is
Object of class stdClass could not be converted to string