Извлечение специфичных для тега данных из документа XML с помощью XPath - PullRequest
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Извлечение специфичных для тега данных из документа XML с помощью XPath

0 голосов
/ 02 октября 2018

Я пытаюсь извлечь данные тега <description> из документа XML, используя DOMDocument и XPath, domXpath.Мне нужны только данные <description>, которым предшествует тег <header id="1236">MECHANICAL</header>.До сих пор я создал это как мой поток xPath;однако при вызове данных не удалось: 

($xpath->query('//VehicleDescription/standard[header="MECHANICAL"]/description')

Я считаю, что проблема заключается в VehicleDescription.Любые идеи о том, как это исправить?Имейте в виду, что это результат Soap, поэтому VehicleDescription и все другие данные по этому вопросу будут меняться при каждом запросе.

<S:Envelope xmlns:S="http://schemas.xmlsoap.org/soap/envelope/">
 <S:Body>
  <VehicleDescription country="US" language="en" modelYear="2015" bestMakeName="Audi" bestModelName="A4" bestStyleName="4dr Sdn Auto quattro 2.0T Premium" bestTrimName="Premium" xmlns="urn:description7b.services.chrome.com">

 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Engine: 2.0L DOHC 4-Cylinder TFSI -inc: Audi valvelift system</description>
    <category id="1048"/>
    <category id="1054"/>
    <category id="1213"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Transmission: 8-Speed Automatic w/Tiptronic -inc: sport program and manual shift mode</description>
    <category id="1130"/>
    <category id="1195"/>
    <category id="1220"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Full-Time All-Wheel Drive</description>
    <category id="1041"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Engine Oil Cooler</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>80-Amp/Hr Maintenance-Free Battery w/Run Down Protection</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>150 Amp Alternator</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Gas-Pressurized Shock Absorbers</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Front And Rear Anti-Roll Bars</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Electric Power-Assist Speed-Sensing Steering</description>
    <category id="1084"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>16.1 Gal. Fuel Tank</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Single Stainless Steel Exhaust</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Multi-Link Front Suspension w/Coil Springs</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>Multi-Link Rear Suspension w/Coil Springs</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1236">MECHANICAL</header>
    <description>4-Wheel Disc Brakes w/4-Wheel ABS, Front Vented Discs, Brake Assist, Hill Hold Control and Electric Parking Brake</description>
    <category id="1018"/>
    <category id="1020"/>
    <category id="1228"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Wheels: 8.0J x 17" 10-Spoke-Star-Design</description>
    <category id="1123"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Tires: P245/45R17 AS</description>
    <category id="1092"/>
    <category id="1097"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Wheels w/Silver Accents</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Steel Spare Wheel</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Compact Spare Tire Mounted Inside Under Cargo</description>
    <category id="1098"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Clearcoat Paint</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Express Open/Close Sliding And Tilting Glass 1st Row Sunroof w/Sunshade</description>
    <category id="1069"/>
    <category id="1132"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Body-Colored Front Bumper</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Body-Colored Rear Bumper</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Rocker Panel Extensions</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Aluminum Side Windows Trim and Black Front Windshield Trim</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Body-Colored Door Handles</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Body-Colored Power Heated Side Mirrors w/Manual Folding and Turn Signal Indicator</description>
    <category id="1064"/>
    <category id="1065"/>
    <category id="1174"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Fixed Rear Window w/Defroster</description>
    <category id="1034"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Light Tinted Glass</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Speed Sensitive Rain Detecting Variable Intermittent Wipers w/Heated Jets</description>
    <category id="1127"/>
    <category id="1159"/>
    <category id="1160"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Galvanized Steel/Aluminum Panels</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Black Grille w/Chrome Surround</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Trunk Rear Cargo Access</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Programmable Projector Beam High Intensity Low/High Beam Daytime Running Auto-Leveling Headlamps w/Washer and Delay-Off</description>
    <category id="1061"/>
    <category id="1168"/>
    <category id="1169"/>
    <category id="1313"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Front And Rear Fog Lamps</description>
    <category id="1151"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Cornering Lights</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>Perimeter/Approach Lights</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1176">EXTERIOR</header>
    <description>LED Brakelights</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="10689">ENTERTAINMENT</header>
    <description>Radio: Audi Concert System w/1CD Player -inc: MP3 capable, AM/FM radio, auxiliary input jack, SD card slots w/32GB capacity for MP3 files, speed-dependent volume control, Audi MMI radio plus system for controlling infotainment/climate/car setup w/6.5" color screen, Audi music interface w/iPod integration w/1 cable for iPod connection, Audi 6-channel DSP extended 180 watt sound system w/10 speakers including subwoofer and SiriusXM satellite radio w/90-day trial subscription</description>
    <category id="1014"/>
    <category id="1017"/>
    <category id="1149"/>
    <category id="1150"/>
    <category id="1230"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="10689">ENTERTAINMENT</header>
    <description>Radio w/Clock and Steering Wheel Controls</description>
    <category id="1161"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="10689">ENTERTAINMENT</header>
    <description>Audio Theft Deterrent</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="10689">ENTERTAINMENT</header>
    <description>Window Grid Diversity Antenna</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="10689">ENTERTAINMENT</header>
    <description>Bluetooth Wireless Phone Connectivity</description>
    <category id="1211"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Power Front Seats -inc: 8-way power front seats and 4-way power lumbar adjustment for driver</description>
    <category id="1074"/>
    <category id="1075"/>
    <category id="1082"/>
    <category id="1189"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Driver Seat</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Passenger Seat</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>60-40 Folding Bench Front Facing Fold Forward Seatback Rear Seat</description>
    <category id="1076"/>
    <category id="1304"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Manual Tilt/Telescoping Steering Column</description>
    <category id="1087"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Gauges -inc: Speedometer, Odometer, Engine Coolant Temp, Tachometer, Oil Level, Trip Odometer and Trip Computer</description>
    <category id="1203"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Power Rear Windows</description>
    <category id="1126"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Leather Steering Wheel</description>
    <category id="1192"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Front Cupholder</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Rear Cupholder</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Front Cigar Lighter(s)</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Ashtray</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Valet Function</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Power Fuel Flap Locking Type</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Remote Keyless Entry w/Integrated Key Transmitter, 4 Door Curb/Courtesy, Illuminated Entry and Panic Button</description>
    <category id="1062"/>
    <category id="1063"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Remote Releases -Inc: Power Cargo Access</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>HomeLink Garage Door Transmitter</description>
    <category id="1204"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Cruise Control</description>
    <category id="1033"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Dual Zone Front Automatic Air Conditioning</description>
    <category id="1009"/>
    <category id="1010"/>
    <category id="1011"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Rear HVAC w/Separate Controls</description>
    <category id="1011"/>
    <category id="1012"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>HVAC -inc: Underseat Ducts and Console Ducts</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Illuminated Locking Glove Box</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Driver Foot Rest</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Interior Trim -inc: Aluminum Instrument Panel Insert, Aluminum Door Panel Insert, Aluminum Console Insert and Aluminum/Metal-Look Interior Accents</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Full Cloth Headliner</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Leatherette Door Trim Insert</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Leather Gear Shift Knob</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Leather Seating Surfaces</description>
    <category id="1078"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Day-Night Rearview Mirror</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Driver And Passenger Visor Vanity Mirrors w/Driver And Passenger Illumination</description>
    <category id="1175"/>
    <category id="1176"/>
    <category id="1177"/>
    <category id="1178"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Full Floor Console w/Storage, Mini Overhead Console w/Storage and 3 12V DC Power Outlets</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Front And Rear Map Lights</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Fade-To-Off Interior Lighting</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Full Carpet Floor Covering -inc: Carpet Front And Rear Floor Mats</description>
    <category id="1055"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Carpet Floor Trim and Carpet Trunk Lid/Rear Cargo Door Trim</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Cargo Space Lights</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>FOB Controls -inc: Trunk/Hatch/Tailgate, Windows and Sunroof/Convertible Roof</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Driver / Passenger And Rear Door Bins</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Power 1st Row Windows w/Front And Rear 1-Touch Up/Down</description>
    <category id="1126"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Delayed Accessory Power</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Power Door Locks w/Autolock Feature</description>
    <category id="1063"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Systems Monitor</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Redundant Digital Speedometer</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Trip Computer</description>
    <category id="1203"/>
    <styleId>369101</styleId>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Outside Temp Gauge</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Analog Display</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Manual Anti-Whiplash Adjustable Front Head Restraints and Manual Adjustable Rear Head Restraints</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Front Center Armrest and Rear Center Armrest w/Storage</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>2 Seatback Storage Pockets</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Perimeter Alarm</description>
    <category id="1013"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Immobilizer III Engine Immobilizer</description>
    <category id="1166"/>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>3 12V DC Power Outlets</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>
 <standard>
    <header id="1220">INTERIOR</header>
    <description>Air Filtration</description>
    <styleId>369101</styleId>
    <installed cause="BaseEquipment"/>
 </standard>

</VehicleDescription>

Вот мой php: 

<!DOCTYPE html>
 <html lang="en">

 <head>
 <title>Dynamically Generate Select Dropdowns 2</title>
 <style type="text/css">
   select {display: block;margin-left: auto;margin-right: auto;}
 </style>
 </head>

 <body>

   <?php

     $xml = file_get_contents('note.xml');
     $dom = new DOMDocument();
     $dom->loadXML($xml);
     $xpath = new domXpath($dom);

     foreach ($xpath->query('//VehicleDescription/standard[header="MECHANICAL"]/description') as $mechdescription) {
     $mecharray[] = $mechdescription->nodeValue ;
     }

     foreach ($mecharray as $mechanicaldescription){
     echo $mechanicaldescription ."\n\n";
     }
  ?>

 </body>
 </html>

Большое спасибо за вашу помощь!

1 Ответ

0 голосов
/ 02 октября 2018

Поскольку узел <VehicleDescription> определяет свое собственное пространство имен по умолчанию (в xmlns="urn:description7b.services.chrome.com"), вам необходимо зарегистрировать это пространство имен и использовать его как часть выражения XPath ... 

$xpath = new DOMXPath($dom);
$xpath->registerNamespace("def", "urn:description7b.services.chrome.com");
$mecharray = [];
foreach ($xpath->query('//def:VehicleDescription/def:standard[def:header="MECHANICAL"]/def:description') as $mechdescription) {
    $mecharray[] = $mechdescription->nodeValue ;
}

Iиспользуйте def в качестве префикса пространства имен, но вы можете использовать все, что захотите, если оно совпадает с выражением XPath.

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