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And PHP version to 5.5.3

When you treat objects as arrays, PHP mangles the names of protected and private members - it's not like you're supposed to have access to them anyways. Private members are mangled to "\0(class)\0(name)" and protected members to "\0*\0(name)".

Your code needs
  $test = "\0Exception\0trace";
to match correctly.

I don't know the true purpose of your script nor what all obj2xml() needs to expose in the XML but you should probably be using get_object_vars [http://www.php.net/get-object-vars] instead of treating objects as arrays (like you're doing with the while/list/each). Such as

  function obj2xml($v, $indent='') {
      if (is_object($v)) { $v = get_object_vars($v); }

However it won't expose to you members you shouldn't have access to; calling it from outside the class will only give you the public members, and Exception does not have any.

The purpose of this page is to expose as much information related to any error that may occur in XML format to my C# windows service that is making the calls.

I made a C# windows service to make HttpWebRequests to my PHP server on a specified schedule based on certain OS/Hardware parameters for instance if a Hard Drive starts getting full it will call a script to remove older records etc. I wanted to find a way if an error occurs in my PHP script to get as much information about the error to my service so it can log it in the windows event log

but my the XML returned was showing that Exceptiontrace or really "\0Exception\0trace" was malformed. 

Thanks for your help with this, After doing a little research would just running $key = preg_replace( '/[^[:print:]]/', '',$key); work for removing all hidden characters? or would you recommend completely changing the way I've got it set up

My first instinct would be to use special handling for specific classes, such as Exception, and get_object_vars() for the rest.

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