Trying to get property of non-object in Error

[bravo14]

Hi Guys

 

Trying to get xml elements to display in a html table using the following code

<?php
session_start();
include_once('includes/connect_inc.php');
$file="https://www.cdlvis.com/lookup/getxml?username=username&mode=test&key=password&vrm=".$_POST['veh_reg']."";
$dom=new DOMdocument();
$dom->load($file);
$xml=simplexml_import_dom($dom);
?>

 

and

 

<form name="vehicle_details" method="post" action="add_vehicle.php">
<table>
<tr>
<td>Registration Number:</td><td><input name="reg_num" type="text" value="<?php echo $xml->result[0]->vrm;?>" readonly="true" /></td></tr>
<tr>
<td>Make:</td><td><input name="make" type="text" value="<?php echo $xml->result[0]->make;?>" readonly="true" /></td></tr>
<tr>
<td>Model:</td><td><input name="model" type="text" value="<?php echo $xml->result[0]->model;?>" readonly="true" /></td></tr>
<tr>
<td>Date of Manufacture:</td><td><input name="date_man" type="text" value="<?php echo $xml->result[0]->date_manufactured;?>" readonly="true" /></td></tr>
<tr>
<td>Date of First Registration:</td><td><input name="date_reg" type="text" value="<?php echo $xml->result[0]->first_registered;?>" readonly="true" /></td></tr>
<tr>
<td>Colour:</td><td><input name="colour" type="text" value="<?php echo $xml->result[0]->colour;?>" readonly="true" /></td></tr>
<tr>
<td>Body Style:</td><td><input name="body" type="text" value="<?php echo $xml->result[0]->body;?>" readonly="true" /></td></tr>
<tr>
<td>Number of Doors:</td><td><input name="doors" type="text" value="<?php echo $xml->result[0]->doors;?>" readonly="true" /></td></tr>
<tr>
<td>Engine Size:</td><td><input name="engine_size" type="text" value="<?php echo $xml->result[0]->engine_size;?>" readonly="true" /></td></tr>
<tr>
<td>Fuel Type:</td><td><input name="fuel_type" type="text" value="<?php echo $xml->result[0]->fuel;?>" readonly="true" /></td></tr>
<tr>
<td>Gearbox Type:</td><td><input name="gearbox" type="text" value="<?php echo $xml->result[0]->gearbox_type;?>" readonly="true" /></td></tr>
<tr>
<td>Previous Keepers:</td><td><input name="keepers" type="text" value="<?php echo $xml->result[0]->previous_keepers;?>" readonly="true" /></td></tr>
<tr>
<td>BHP:</td><td><input name="bhp" type="text" value="<?php echo $xml->result[0]->smmt_power_bhp;?>" readonly="true" /></td></tr>
<tr>
<td>Emissions:</td><td><input name="co2" type="text" value="<?php echo $xml->result[0]->smmt_co2;?>" readonly="true" /></td></tr>
<tr>
<td><input name="try_again" type="button" value="Try Again" /></td><td><input name="submit" type="submit" value="Next Stage" /></td></tr>
</table>
</form>

 

What have I done wrong?