My class implements the 

> 
> jsonSerialize in php
> 
> 
> 

Then my class implements the jsonSerialize method and returns get\_object\_vars($this).

```
 public function JsonSerialize()
{
    $vars = get_object_vars($this);

    return $vars;
}

```

The problem with this is it returns all the values including NULL variables too.
How can I only get the non-null variables as json-output?