如何避免PHP注意"Undefined offset:0"而不检查数组的每个字段

Question

我有以下数组:

    $keyvisual_data = array(
        'video_file'            => $row->field_field_video[0]['rendered']['#item']['uri'],
        'bild_file'             => $row->field_field_bild[0]['rendered']['#item']['uri'],
        'subline_src'           => $row->_field_data['nid']['entity']->field_key_titel['und'][0]['safe_value'],
        'screenreader_src'      => $row->field_field_alt_screenreader[0]['rendered']['#markup'],
        'alt_src'               => $row->field_field_bild[0]['rendered']['#item']['alt']
    );

可能会发生某些字段未设置,这没关系.事实上我得到这个PHP通知:

注意:未定义的偏移量:bafa_insert_keyvisual()中的0 ...........

是否有可能为每个键分配一个默认值,以防它未定义而不用手动检查数组的每个字段？

感谢帮助

Answer 1

不,那里没有

你可以这样做isset():

if(isset($array[0])){
    echo $array[0];
}
else {
  //some error?
}

或者,如果您知道您只是要检查索引0:

$array = $array + array(null);

所以如果原来$array[0]没有设置,现在就是null

Answer 2

是的,@在字段之前添加如下:

$keyvisual_data = array(
    'video_file'            => @$row->field_field_video[0]['rendered']['#item']['uri'],
    'bild_file'             => @$row->field_field_bild[0]['rendered']['#item']['uri'],
    'subline_src'           => @$row->_field_data['nid']['entity']->field_key_titel['und'][0]['safe_value'],
    'screenreader_src'      => @$row->field_field_alt_screenreader[0]['rendered']['#markup'],
    'alt_src'               => @$row->field_field_bild[0]['rendered']['#item']['alt']
);

然后初始化空值:

if($keyvisual_data['video_file'] === null)
    $keyvisual_data['video_file'] = $default_video_file;

等等...