simplexml_load_string命名空间的正确参数

您可以使用子级获取具有名称空间的元素。例如：

<people xmlns:ns="http://something.com/ns">
<person><ns:name>Amy</ns:name></person>
<person><ns:name>Bill</ns:name></person>
</people>
$xml = simplexml_load_string($string);
echo $xml->person[0]->children("http://something.com/ns")->name; // will echo Amy

以下是手册中的说明

PHP.NET

simplexml_load_file ( string $filename [, string $class_name = "SimpleXMLElement" [, int $options = 0 [, string $ns = "" [, bool $is_prefix = false ]]]] )
$xml = simplexml_load_string($val->getResponseBody(),null, 0, 'gd', true);
$xml =json_encode($xml); 

更新

如果您没有正确使用名称空间，请显示所有的xml结构。

在您展示的示例中，没有定义名称空间gd。你需要这样的东西来让它工作：

<item xmlns:gd='http://schemas.google_apps_sync.com'> 
   <gd:extendedProperty xmlns:gs='http://schemas.google_apps_sync.com'..>
   ...
   </gd:extendedProperty>
</item>

现在你可以使用了

$xml = simplexml_load_string($val->getResponseBody(),null, 0, 'gd', true);

当你想访问gs名称空间时，你可以使用

$xml->registerXPathNamespace("gs", 'http://schemas.google_apps_sync.com');

经过数小时的梳理，我发现stackoverflow上的信息和谷歌上相对未记录的信息。。。如果您将?alt=json添加到联系人api uri的末尾，您将收到JSON格式的响应！

这将从所有命名空间加载所有数据：

function xmlToArray($xml, $options = array()) {
    $defaults = array(
        'namespaceSeparator' => ':',//you may want this to be something other than a colon
        'attributePrefix' => '@',   //to distinguish between attributes and nodes with the same name
        'alwaysArray' => array(),   //array of xml tag names which should always become arrays
        'autoArray' => true,        //only create arrays for tags which appear more than once
        'textContent' => '$',       //key used for the text content of elements
        'autoText' => true,         //skip textContent key if node has no attributes or child nodes
        'keySearch' => false,       //optional search and replace on tag and attribute names
        'keyReplace' => false       //replace values for above search values (as passed to str_replace())
    );
    $options = array_merge($defaults, $options);
    $namespaces = $xml->getDocNamespaces();
    $namespaces[''] = null; //add base (empty) namespace
    //get attributes from all namespaces
    $attributesArray = array();
    foreach ($namespaces as $prefix => $namespace) {
        foreach ($xml->attributes($namespace) as $attributeName => $attribute) {
            //replace characters in attribute name
            if ($options['keySearch']) $attributeName =
                   str_replace($options['keySearch'], $options['keyReplace'], $attributeName);
            $attributeKey = $options['attributePrefix']
                    . ($prefix ? $prefix . $options['namespaceSeparator'] : '')
                    . $attributeName;
            $attributesArray[$attributeKey] = (string)$attribute;
 
        }
 
    }
 
  
 
    //get child nodes from all namespaces
 
    $tagsArray = array();
 
    foreach ($namespaces as $prefix => $namespace) {
 
        foreach ($xml->children($namespace) as $childXml) {
 
            //recurse into child nodes
 
            $childArray = xmlToArray($childXml, $options);
 
            list($childTagName, $childProperties) = each($childArray);
 
  
 
            //replace characters in tag name
 
            if ($options['keySearch']) $childTagName =
 
                    str_replace($options['keySearch'], $options['keyReplace'], $childTagName);
 
            //add namespace prefix, if any
 
            if ($prefix) $childTagName = $prefix . $options['namespaceSeparator'] . $childTagName;
 
  
 
            if (!isset($tagsArray[$childTagName])) {
 
                //only entry with this key
 
                //test if tags of this type should always be arrays, no matter the element count
 
                $tagsArray[$childTagName] =
 
                        in_array($childTagName, $options['alwaysArray']) || !$options['autoArray']
 
                        ? array($childProperties) : $childProperties;
 
            } elseif (
 
                is_array($tagsArray[$childTagName]) && array_keys($tagsArray[$childTagName])
 
                === range(0, count($tagsArray[$childTagName]) - 1)
 
            ) {
 
                //key already exists and is integer indexed array
 
                $tagsArray[$childTagName][] = $childProperties;
 
            } else {
 
                //key exists so convert to integer indexed array with previous value in position 0
 
                $tagsArray[$childTagName] = array($tagsArray[$childTagName], $childProperties);
 
            }
 
        }
 
    }
 
  
 
    //get text content of node
 
    $textContentArray = array();
 
    $plainText = trim((string)$xml);
 
    if ($plainText !== '') $textContentArray[$options['textContent']] = $plainText;
 
  
 
    //stick it all together
 
    $propertiesArray = !$options['autoText'] || $attributesArray || $tagsArray || ($plainText === '')
 
            ? array_merge($attributesArray, $tagsArray, $textContentArray) : $plainText;
 
    //return node as array
    return array(
        $xml->getName() => $propertiesArray
    );
}