在Drupal 8中从术语实体引用抓取字段时尝试获取非对象的属性

Question

我正在创建一个内容类型传记的XML提要，其中包含实体引用术语字段。我正在加载节点，加载段落字段，然后使用Term::load在段落字段中加载term对象，这是一个按术语ID编号的术语。但是，当我试图从术语本身获取字段时，我必须在使用->name->value的行上抛出“尝试获取非对象的属性”。字段成功地被抓取和渲染，错误也随之而来。尝试使用->getName()方法会完全破坏提要。

private function xmlOutput($input) {
  $node = Node::load($input);
  $educationArray = $node->get('field_group_education');
  $educationOutput = [];
  foreach ($educationArray as $key => $value) {
    $educationGroupID = $node->get('field_group_education')[$key]->target_id;
    $educationGroup = Paragraph::load($educationGroupID);
    $honors = $educationGroup->get('field_academic_honors')->value;
    $degreeID = $educationGroup->get('field_degrees')->target_id;
    $degree = Term::load($degreeID)->name->value;
    $educationID = $educationGroup->get('field_education')->target_id;
    $schoolName = Term::load($educationID)->name->value;
    $yearGraduated = $educationGroup->get('field_year_graduated')->value;
    $educationRender = '<professionalEducation>
                        <order>' . $key  . '</order>
                        <school whereField="Name" whereValue="' . $schoolName . '" autoCreate="true"/>
                        <educationType whereField="Name" whereValue="' . $degree . '" autoCreate="true"/>
                        <yearGraduated>' . $yearGraduated . '</yearGraduated>
                        <degree whereField="Name" whereValue="' . $degree . '" autoCreate="true"/> . 
                        <honors>' . $honors . '</honors>
                        </professionalEducation>';
    array_push($educationOutput, $educationRender);
  }
  $compiled = [
    '<education>',
    implode($educationOutput),
    '</education>',
  ];
  return implode('', $compiled);

}

这将成功地呈现

<education>
  <professionalEducation>
    <order>0</order>
    <school whereField="Name" whereValue="education term 1" 
    autoCreate="true"/>
    <educationType whereField="Name" whereValue="AA" autoCreate="true"/>
    <yearGraduated>1990</yearGraduated>
    <degree whereField="Name" whereValue="AA" autoCreate="true"/>
    <honors>Honors 1</honors>
  </professionalEducation>
  <professionalEducation>
    <order>1</order>
    <school whereField="Name" whereValue="education term 2" autoCreate="true"/>
    <educationType whereField="Name" whereValue="AB" autoCreate="true"/>
    <yearGraduated>2000</yearGraduated>
    <degree whereField="Name" whereValue="AB" autoCreate="true"/>
    <honors>honors 2</honors>
  </professionalEducation>
</education>

但是，对于使用->getName()方法尝试获取->name->value的行，我得到了“试图获取非对象属性”的PHP错误，但这会立即引发500个错误。使用isset检查是否有一个值在使getName()工作时也不起作用。

$degree = '';
if(isset(Term::load($degreeID)->name->value)) {
  $degree = $degreeObject->name->value;
}

工作，但错误仍然存在

$degree = '';
if(isset(Term::load($degreeID)->getName())) {
  $degree = $degreeObject->getName();
}

抛出500错误，但也消除错误

Answer 1

检查target_id isset()。按以下方式修改代码

  $educationGroup = $value->entity;
  $honors = isset($educationGroup->field_academic_honors->target_id) ? $educationGroup->field_academic_honors->value : '';
  $degree = isset($educationGroup->field_degrees->target_id) ? $educationGroup->field_degrees->entity->name->value : '';
  $schoolName = isset($educationGroup->field_education->target_id) ? $educationGroup->field_education->entity->name->value : '';
  $yearGraduated = isset($educationGroup->field_year_graduated->target_id) ? $educationGroup->field_year_graduated->value : '';

每次您可以使用引用获得它们时，不需要加载段和术语。